night-biter UK /naɪt ˈbaɪtə/US /naɪt ˈbaɪtɚ/ noun1 •An animal, especially an insect such as a mosquito, that bites during the night.She [the mosquito] may be a night-biter or a day-biter. She may give an alarm: a hum made by the beating of her wings. Or she may be absolutely silent. — 1954 formsnight biters · night-biters