Imperfectly or partly heard; not heard to the end.(adjective)
Gnu Collaboartive International Dictionary of English: licensed under The Code Project Open License (CPOL)
Use "half-heard" in a sentence
"The curve of light bends back over him, dips with a supersonic roar, then turns and climbs toward the lower stars with a faint, half-heard shout: Away!"
"It's as if she hadn't been paying attention at the crucial moment and only half-heard him and she doesn't want him to know."
"I gathered from their half-heard conversation that Beefy was lamenting the loss of a lock of hair belonging to some bint called Leni which he'd carried in the back of his watch, and getting scant sympathy; Prussians, you know, care not two dams about their inferiors."