Examples from the Web for semi-nocturnal
Probably they are semi-nocturnal, and able to see in dark places as well as in the night.Reptiles and Birds|Louis Figuier
The eye itself has a dark-brown iris, with the round pupil that indicates diurnal or at least semi-nocturnal habits.
British Dictionary definitions for semi-nocturnal
Word Origin for nocturnal
Word Origin and History for semi-nocturnal
late 15c., from Old French nocturnal "nightly, nocturnal," or directly from Late Latin nocturnalis, from Latin nocturnus "belonging to the night," from nox (genitive noctis) "night," cognate with Old English neaht (see night) + -urnus, suffix forming adjectives of time. Nocturnal emission "involuntary ejaculation during sleep" first recorded 1813.