from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Of, relating to, or occurring in the night: nocturnal stillness.
- adj. Botany Having flowers that open during the night.
- adj. Zoology Most active at night: nocturnal animals.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. Primarily active during the night.
- adj. Taking place at night.
from the GNU version of the Collaborative International Dictionary of English
- adj. Of, pertaining to, done or occuring in, the night; ; -- opposed to
- adj. Having a habit of seeking food or moving about at night; ; -- of animals.
- n. An instrument formerly used for taking the altitude of the stars, etc., at sea.
from The Century Dictionary and Cyclopedia
- Of or pertaining to the night; belonging to the night; used, done, or occurring at night: as, nocturnal cold; a nocturnal visit: opposed to diurnal.
- Of or pertaining to a nocturn.
- In zoology, active by night: as, nocturnal lepidopter.
- Syn. 1 and See nightly.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adj. belonging to or active during the night
- adj. of or relating to or occurring in the night
Middle English, from Old French, from Late Latin nocturnālis, from Latin nocturnus, from nox, noct-, night; see nekw-t- in Indo-European roots.(American Heritage® Dictionary of the English Language, Fourth Edition)