adjective

(1) Consisting of one of two equivalent parts in value or quantity

(2) Partial

(3) (of siblings) related through one parent only

noun

(1) Either of two equal or corresponding parts into which something is or can be divided.

(2) One of two equal parts of a divisible whole

(3) In various games or performances: either of two periods of play separated by an interval

adverb

(1) Partially or to the extent of a half