weight 
(wāt)
(wāt)n. Abbr. wt. or w
1. A measure of the heaviness of an object: a contest to guess the weight of a pig.
2. The force with which a body is attracted to Earth or another celestial body, equal to the product of the object's mass and the acceleration of gravity.
3.
a. A unit measure of gravitational force: a table of weights and measures.
b. A system of such measures: avoirdupois weight; troy weight.
4. An object used principally to exert a force by virtue of its gravitational attraction to Earth, especially:
a. A metallic solid used as a standard of comparison in weighing.
b. An object used to hold something else down.
c. A counterbalance in a machine.
d. Sports A heavy object, such as a dumbbell, lifted for exercise or in athletic competition.
5. Excessive fat; corpulence: exercising in order to lose weight.
6. Statistics A factor assigned to a number in a computation, as in determining an average, to increase or decrease the number's effect on the computation, reflecting its importance.
7. Oppressiveness; pressure: the weight of responsibilities.
8. The greater part; preponderance: The weight of the evidence is against the defendant.
9.
a. Influence, importance, or authority: Her approval carried great weight. See Synonyms at importance.
b. Ponderous quality: the weight of the speaker's words.
10. Sports A classification according to comparative lightness or heaviness. Often used in combination: a heavyweight boxer.
11.
a. The heaviness or thickness of a fabric in relation to a particular season or use. Often used in combination: a summerweight jacket.
b. A measure of the relative thickness of yarn.
tr.v. weight·ed, weight·ing, weights
Idioms: 1. To make heavy or heavier: Our backpacks were weighted down with food and other essentials.
2. To cause to feel concerned, sad, or preoccupied; burden or oppress: He was weighted with guilt.
3. To increase the weight or body of (fabrics) by treating with chemicals.
4. Statistics To assign weights or a weight to.
5. To cause to have a slant or bias: weighted the rules in favor of homeowners.
6. Sports To assign to (a horse) the weight it must carry as a handicap in a race.
by weight
According to weight rather than volume or other measure.
make weight
Sports To weigh within the limits stipulated for an athletic contest.
[Middle English wight, from Old English wiht; see wegh- in the Appendix of Indo-European roots.]