HALF

n. one part of two equal parts; one of a pair; either of two equal playing periods in a game (Sports); halfway point in playing time (Sports); halfback (Football)

adv. partially

adj. being one of two equal parts; partial, not complete; having one parent in common

v. halve, share equally, divide into two

One half is the irreducible fraction resulting from dividing one by two (½), or any number by its double; multiplication by one half is equivalent to  division by two. It is the fraction occurring most often in mathematical equations, recipes, measurements, etc. Half can also be said to be one part of something divided into two equal parts.
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Noun
1. one of two equal parts of a divisible whole; "half a loaf"; "half an hour"; "a century and one half"
(synonym) one-half
(hypernym) common fraction, simple fraction
(hyponym) fifty percent
2. in various games or performances: either of two periods of play separated by an interval
(hypernym) playing period, period of play, play
(hyponym) first half
(part-holonym) football, football game
Adjective
1. consisting of one of two equivalent parts in value or quantity; "a half chicken"; "lasted a half hour"
(synonym) half(a)
(similar) fractional
2. partial; "gave me a half smile"; "he did only a half job"
(synonym) half(a)
(similar) incomplete, uncomplete
3. (of siblings) related through one parent only; "a half brother"; "half sister"
(antonym) whole
Adverb
1. partially or to the extent of a half; "he was half hidden by the bushes"
(pertainym) half(a)

v. help, assist, aid, lend a hand, come to the aid of, give assistance

adv. half, partially

adj. half

half, one part of two equal parts; one of a pair; either of two equal playing periods in a game