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1. Of, relating to, or occurring in the night: nocturnal stillness.
2. Botany Opening at night. Used of flowers.
3. Zoology Most active at night: nocturnal lizards.

[Middle English, from Old French, from Late Latin nocturnālis, from Latin nocturnus, from nox, noct-, night; see nekw-t- in Indo-European roots.]

noc·tur′nal·ly adv.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adv.1.nocturnally - at night; "nocturnally active bird"
References in periodicals archive ?
kershawi is nocturnally active and is herbivorous, grazing on fungi and decaying plant material (Stanisic et al.
The nighttime observations in the darkness of the early evening were made by DHD to encounter nocturnally active crabs that had left their aquatic habitats to feed on land.
For example, root voles Microtus oeconomus have been found to be more nocturnally active in years of high abundances of weasels Mustela nivalis, which are mostly diurnal (Gliwicz & Dabrowski 2008).
This mammalian species is terrestrial, placental mammal and nocturnally active.
nocturnally); displaced geese may end up concentrated in smaller areas.
Following previous research that demonstrated that feral hogs were more active during crepuscular and nocturnal periods, we predicted that hogs in northern Texas would also be more active during nocturnal periods, spending more time in areas providing cover diurnally and in more open land nocturnally when mobile.
She adds that by her second year at university she became "so afraid of sleep" that she spent a whole term living nocturnally.
An open-label polysomnographic study reported that nocturnally administered sodium oxybate improved subjective sleepiness, sleep quality, and fatigue as well as slow wave sleep in PD patients.[79] Recently, a randomized, double-blind, placebo-controlled, crossover, Phase IIA study reported that sodium oxybate was effective in treating EDS and nocturnal sleep disturbance with Class I evidence.
Certain nocturnally migrating insects can explore and navigate using the Earth's magnetic field, according to an intemational study led by researchers from Sweden's Lund University.
When pigs are nocturnally active, recreational hunting would only be an effective pig control strategy in agricultural fields, as some have suggested (Geisser and Reyer 2004; Hone and Atkinson 1983), if regulations allowed hunting at night.
Although they are closely related to nocturnally flashing species, winter fireflies lack light organs; males are attracted to females by odors.
Lots of wallowing and waterhole activity happens nocturnally, especially on heavily hunted ground.