Douglas Harper's Etymology Dictionary
half-
"sharing one parent," from half. Half-brother is attested from early 14c.; half-sister from c.1200.
Wiktionary
Usage examples of "half-".
The half- obscured sunset showed through a narrow band of sky under the encroaching, nimbus-filled overcast that was again heavy with storm and with snow.
He was half- sitting against several pillows, his knees up, and his hands lying lightly on them, the fingers curved.
She took the half- burned candles out of the heavy branched candlestick.
No one made any movement to clear the tables, which were still covered with dirty trenchers and half- full serving bowls.