ETYM as. healf, half, half; as a noun, half, side, part; akin to os., OFries., and Dutch half, German halb, Swed. half, Dan. halv, Icel. hâlfr, Goth. halbs. Related to Halve, Behalf.
(Of siblings) Related through one parent only.
1. Consisting of one of two equivalent parts in value or quantity.
2. Partial.

Partially or to the extent of a half

ETYM as. healf. Related to Half.
(Irregular plural: halves).
In various games or performances: either of two periods of play separated by an interval.