One of two usually roughly equal parts into which anything may be divided, or considered as divided.

(sports) One of the two opposite parts of the playing field of various sports, in which each starts the game.

Half of a standard measure, chiefly: (Britain) half a pint of beer or cider. (Refusing a pint) Just a half, thank you. (Offering to top up a pint glass) Do you want a half in that? (Minimizing the amount of drink taken) A swift half at the Pear Tree.

(preceded by “a” or a number) The fraction obtained by dividing 1 by 2.

Any of the three terms at Eton College, for Michaelmas, Lent, and summer.

(slang) A half sibling.

(UK, dated) A child ticket. Two and a half to Paddington.

(sports) abbreviated form for half marathon.

(numismatic slang) Clipping of half-dollar.

(transitive, obsolete) To halve.

Consisting of a half (½, 50%).

Consisting of some indefinite portion resembling a half; approximately a half, whether more or less; partial; imperfect.

(of a sibling) Having one parent (rather than two) in common.

(of a relative other than a sibling) Related through one common grandparent or ancestor rather than two.

(UK, Ireland) Half past; a half-hour (30 minutes) after the last hour.

(Discuss(+) this sense) (rare, see usage notes) A half-hour to (preceding) the next hour.

In two equal parts or to an equal degree.

In some part approximating a half.

Partially; imperfectly.

Practically, nearly.

(theater) A call reminding performers that the performance will begin in thirty minutes.