Weigh \Weigh\, n. [See Wey.] A certain quantity estimated by weight; an English measure of weight. See Wey. [1913 Webster]
Weigh \Weigh\, v. t. [imp. & p. p. Weighed; p. pr. & vb. n. Weighing.] [OE. weien, weyen, weghen, AS. wegan to bear, move; akin to D. wegen to weigh, G. w[aum]gen, wiegen, to weigh, bewegen to move, OHG. wegan, Icel. vega to move, carry, lift, weigh, Sw. v[aum]ga to weigh, Dan. veie, Goth. gawigan to shake, L. vehere to carry, Skr. vah. ????. See Way, and cf. Wey.] [1913 Webster]
To bear up; to raise; to lift into the air; to swing up; as, to weigh anchor. "Weigh the vessel up." --Cowper. [1913 Webster]
To examine by the balance; to ascertain the weight of, that is, the force with which a thing tends to the center of the earth; to determine the heaviness, or quantity of matter of; as, to weigh sugar; to weigh gold. [1913 Webster] Thou art weighed in the balances, and art found wanting. --Dan. v.
To be equivalent to in weight; to counterbalance; to have the heaviness of. "A body weighing divers ounces." --Boyle. [1913 Webster]
To pay, allot, take, or give by weight. [1913 Webster] They weighed for my price thirty pieces of silver. --Zech. xi.
To examine or test as if by the balance; to ponder in the mind; to consider or examine for the purpose of forming an opinion or coming to a conclusion; to estimate deliberately and maturely; to balance. [1913 Webster] A young man not weighed in state affairs. --Bacon. [1913 Webster] Had no better weighed The strength he was to cope with, or his own. --Milton. [1913 Webster] Regard not who it is which speaketh, but weigh only what is spoken. --Hooker. [1913 Webster] In nice balance, truth with gold she weighs. --Pope. [1913 Webster] Without sufficiently weighing his expressions. --Sir W. Scott. [1913 Webster]
To consider as worthy of notice; to regard. [Obs. or Archaic] "I weigh not you." --Shak. [1913 Webster] All that she so dear did weigh. --Spenser. [1913 Webster] To weigh down. (a) To overbalance. (b) To oppress with weight; to overburden; to depress. "To weigh thy spirits down." --Milton. [1913 Webster]
Weigh \Weigh\, v. i.
To have weight; to be heavy. "They only weigh the heavier." --Cowper. [1913 Webster]
To be considered as important; to have weight in the intellectual balance. [1913 Webster] Your vows to her and me . . . will even weigh. --Shak. [1913 Webster] This objection ought to weigh with those whose reading is designed for much talk and little knowledge. --Locke. [1913 Webster]
To bear heavily; to press hard. [1913 Webster] Cleanse the stuffed bosom of that perilous stuff Which weighs upon the heart. --Shak. [1913 Webster]
To judge; to estimate. [R.] [1913 Webster] Could not weigh of worthiness aright. --Spenser. [1913 Webster] To weigh down, to sink by its own weight. [1913 Webster]
1 have a certain weight
2 show consideration for; take into account; "You must consider her age"; "The judge considered the offender's youth and was lenient" [syn: consider, count]
3 determine the weight of; "The butcher weighed the chicken" [syn: librate]
5 to be oppressive or burdensome; "weigh heavily on the mind", "Something pressed on his mind" [syn: press]
Moby Thesaurusamount to something, analogize, appraise, appreciate, assay, assess, assimilate, balance, be abstracted, be featured, be heavy, be influential, be persuasive, be prominent, be somebody, be something, bring into analogy, bring into comparison, brood, calculate, calibrate, caliper, carry, carry weight, catalog, categorize, charge, check a parameter, chew the cud, class, classify, compare, compare and contrast, compare with, compute, confront, consider, contemplate, contrast, count, counterbalance, counterpose, cumber, cut ice, cut some ice, debate, deliberate, dial, digest, divide, draw a comparison, draw a parallel, encumber, estimate, evaluate, excogitate, factor, fathom, gauge, get top billing, graduate, group, have an in, have full play, have influence, have personality, have pull, have weight, heft, hold the scales, identify, import, introspect, lade, lie heavy, liken, liken to, load, lumber, match, matter, measure, measure against, meditate, mensurate, metaphorize, mete, meter, militate, mind, muse, oppose, pace, parallel, perpend, place against, play around with, play with, plumb, ponder, prize, probe, quantify, quantize, rate, reflect, register, relate, ruminate, run a comparison, saddle, set in contrast, set in opposition, set off against, set over against, sift, signify, similize, size, size up, sort, sort out, sound, span, speculate, stand out, star, step, strike a balance, study, survey, take a reading, tax, tell, think over, thrash out, tip the scales, toy with, triangulate, valuate, value, view together, weigh against, weigh heavy, weigh in, weigh out, weight, winnow
- , /weɪ/, /weI/
- To determine the weight of an object.
- Often with "out", to measure a certain amount of something by
its weight, e.g. for sale.
- He weighed out two kilos of oranges for a client.
- In the context of "transitive|metaphorical": To determine the
intrinsic value or merit of an object, to evaluate.
- You have been weighed in the balance and found wanting.
- To consider a subject.
- To have a certain weight.
- I weigh ten and a half stone.
- In the context of "nautical|transitive": To raise an anchor free of the seabed.
to determine the weight of an object
to weigh out
to determine the intrinsic value or merit of an object
to consider a subject
to have a certain weight
- Finnish: painaa
- French: peser
- Russian: весить (v'ésit')
- Swedish: väga
nautical: to raise an anchor
Weight and mass
In modern scientific usage, weight and mass are fundamentally different quantities: mass is an intrinsic property of matter, whereas weight is a force that results from the action of gravity on matter: it measures how strongly gravity pulls on that matter.
However, the recognition of this difference is, historically, a relatively recent development and in many everyday situations the word "weight" continues to be used when "mass" is meant. For example, we say that an object "weighs one kilogram", even though the kilogram is a unit of mass.
The distinction between mass and weight is unimportant for many practical purposes because the strength of gravity is very simliar everywhere on the surface of the Earth. In such a constant gravitational field, the gravitational force exerted on an object (its weight) is directly proportional to its mass. So, if object A weighs, say, 10 times as much as object B, then object A's mass is 10 times that of object B. This means that an object's mass can be measured indirectly by its weight (for conversion formulas see below). For example, when we buy a bag of sugar we can measure its weight (how hard it presses down on the scales) and be sure that this will give a good indication of the quantity that we are actually interested in, which is the mass of sugar in the bag. Nevertheless, slight variations in the Earth's gravitational field do exist (see Earth's gravity). These alter the relationship between weight and mass, and must be taken into account in high precision weight measurements that are intended to indirectly measure mass.
The use of "weight" for "mass" also persists in some scientific terminology – for example, in the chemical terms "atomic weight", "molecular weight", and "formula weight", rather than the preferred "atomic mass" etc.
The difference between mass and force becomes obvious when:
- objects are compared in different gravitational fields, such as away from the Earth's surface. For example, on the surface of the Moon, gravity is only about one-sixth as strong as on the surface of the Earth. A one-kilogram mass is still a one-kilogram mass (as mass is an intrinsic property of the object) but the downward force due to gravity is only one-sixth of what the object would experience on Earth.
- locating the center of gravity of an object (although if the gravitation field is uniform, the center of gravity will coincide with the center of mass).
- an object is submersed in a fluid (for instance, a brick weighs less when placed in water, and helium balloon in the atmosphere appears to have negative weight).
Units of weight
Systems of units of weight (force) and mass have a tangled history, partly because the distinction was not properly understood when many of the units first came into use.
SI unitsIn most modern scientific work, physical quantities are measured in SI units. The SI unit of mass (and hence weight in some everyday senses) is the kilogram. The SI unit of force (and hence weight in the mechanics sense) is the newton (N) – which can also be expressed in SI base units as kg·m/s² (kilograms times metres per second squared).
The gravitational force exerted on an object is proportional to the mass of the object, so it is reasonable to think of the strength of gravity as measured in terms of force per unit mass, that is, newtons per kilogram (N/kg). However, the unit N/kg resolves to m/s²; (metres per second per second), which is the SI unit of acceleration, and in practice gravitational strength is usually quoted as an acceleration.
The pound and other non-SI units
In United States customary units, the pound can be either a unit of force or a unit of mass. Related units used in some distinct, separate subsystems of units include the poundal and the slug. The poundal is defined as the force necessary to accelerate a one-pound object at 1 ft/s², and is equivalent to about 1/32 of a pound (force). The slug is defined as the amount of mass that accelerates at 1 ft/s² when a pound of force is exerted on it, and is equivalent to about 32 pounds (mass).
The kilogram-force is a non-SI unit of force, defined as the force exerted by a one-kilogram mass in standard Earth gravity (equal to 9.80665 newtons exactly). The dyne is the cgs unit of force and is not a part of SI, while weights measured in the cgs unit of mass, the gram, remain a part of SI.
Conversion between weight (force) and massTo convert between weight (force) and mass we use Newton's second law, F = ma (force = mass × acceleration). Here, F is the force (weight) due to gravity, m is the mass of the object in question, and a is the acceleration due to gravity, on Earth approximately 9.8 m/s² or 32.2 ft/s². In this context the same equation is often written as W = mg, with W standing for weight, and g for the acceleration due to gravity.
Sensation of weightsee also apparent weight The weight force that we actually sense is not the downward force of gravity, but the normal force (an upward contact force) exerted by the surface we stand on, which opposes gravity and prevents us falling to the center of the Earth. This normal force, called the apparent weight, is the one that is measured by a spring scale.
For a body supported in a stationary position, the normal force balances the earth's gravitational force, and so apparent weight has the same magnitude as actual weight. (Technically, things are slightly more complicated. For example, an object immersed in water weighs less, according to a spring scale, than the same object in air; this is due to buoyancy, which opposes the weight force and therefore generates a smaller normal. These and other factors are explained further under apparent weight.)
If there is no contact with any surface to provide such an opposing force then there is no sensation of weight (no apparent weight). This happens in free-fall, as experienced by sky-divers (until they approach terminal velocity) and astronauts in orbit, who feel "weightless" even though their bodies are still subject to the force of gravity: they're just no longer resisting it. The experience of having no apparent weight is also known as microgravity.
A degree of reduction of apparent weight occurs, for example, in elevators. In an elevator, a spring scale will register a decrease in a person's (apparent) weight as the elevator starts to accelerate downwards. This is because the opposing force of the elevator's floor decreases as it accelerates away underneath one's feet.
- Main article: Weighing scale
Weight is commonly measured using one of two methods. A spring scale or hydraulic or pneumatic scale measures weight force (strictly apparent weight force) directly. If the intention is to measure mass rather than weight, then this force must be converted to mass. As explained above, this calculation depends on the strength of gravity. Household and other low precision scales that are calibrated in units of mass (such as kilograms) assume roughly that standard gravity will apply. However, although nearly constant, the apparent or actual strength of gravity does in fact vary very slightly in different places on the earth (see standard gravity, physical geodesy, gravity anomaly and gravity). This means that same object (the same mass) will exert a slightly different weight force in different places. High precision spring scales intended to measure mass must therefore be calibrated specifically according their location on earth.
Mass may also be measured with a balance, which compares the item in question to others of known mass. This comparison remains valid whatever the local strength of gravity. If weight force, rather than mass, is required, then this can be calculated by multiplying mass by the acceleration due to gravity – either standard gravity (for everyday work) or the precise local gravity (for precision work).
Gross weight is a term that generally is found in commerce or trade applications, and refers to the gross or total weight of a product and its packaging. Conversely, net weight refers to the intrinsic weight of the product itself, discounting the weight of packaging or other materials.
Relative weights on the Earth, other planets and the MoonThe table below shows comparative gravitational accelerations at the surface of the Sun, the Earth's moon, each of the planets in the solar system, and Pluto. The “surface” is taken to mean the cloud tops of the gas giants (Jupiter, Saturn, Uranus and Neptune). For the Sun, the surface is taken to mean the photosphere. The values in the table have not been de-rated for the centrifugal effect of planet rotation (and cloud-top wind speeds for the gas giants) and therefore, generally speaking, are similar to the actual gravity that would be experienced near the poles.
weigh in Afrikaans: Gewig
weigh in Arabic: وزن
weigh in Asturian: Pesu
weigh in Bengali: ওজন (ভার)
weigh in Min Nan: Tāng-liōng
weigh in Belarusian: Вага
weigh in Bosnian: Težina
weigh in Bulgarian: Тегло
weigh in Catalan: Pes
weigh in Czech: Váha
weigh in Danish: Vægt (fysik)
weigh in German: Gewicht
weigh in Estonian: Kaal
weigh in Spanish: Peso
weigh in Esperanto: Pezo
weigh in Basque: Pisu
weigh in Persian: وزن
weigh in French: Poids
weigh in Galician: Peso
weigh in Hindi: भार
weigh in Korean: 무게
weigh in Croatian: Težina
weigh in Ido: Pezo
weigh in Indonesian: Berat
weigh in Icelandic: Þyngd
weigh in Italian: Forza peso
weigh in Hebrew: משקל (פיזיקה)
weigh in Latvian: Svars
weigh in Lithuanian: Svoris
weigh in Hungarian: Súly
weigh in Macedonian: Тежина
weigh in Malayalam: ഭാരം
weigh in Malay (macrolanguage): Berat
weigh in Dutch: Gewicht
weigh in Japanese: 重さ
weigh in Norwegian: Tyngde
weigh in Polish: Ciężar
weigh in Portuguese: Peso
weigh in Kölsch: Jeweech
weigh in Romanian: Greutate
weigh in Quechua: Llasaq kay
weigh in Russian: Вес
weigh in Sicilian: Pisu
weigh in Simple English: Weight
weigh in Slovak: Gravitačná hmotnosť
weigh in Slovenian: Teža
weigh in Serbian: Тежина
weigh in Finnish: Paino
weigh in Swedish: Tyngd
weigh in Thai: น้ำหนัก
weigh in Vietnamese: Lực hấp dẫn#Tr.E1.BB.8Dng_l.E1.BB.B1c
weigh in Turkish: Ağırlık
weigh in Ukrainian: Вага
weigh in Yiddish: וואג
weigh in Chinese: 重量