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Related to nocturnal: nocturnal emission, nocturnal enuresis


1. (of animals) active at night
2. (of plants) having flowers that open at night and close by day
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005


(religion, spiritualism, and occult)

Nocturnal means of or belonging to the night. In classical astrology, particular planets were classified as nocturnal or diurnal, no matter where they were in a horoscope. In contemporary astrology, planets are nocturnal if they are located below the horizon (in houses one through six). Many astrologers believe that planets above the horizon line show their influence more in the public sphere whereas planets below the horizon are more private, but this distinction clearly breaks down when considering planets in such locations as the twelfth house (a largely private house situated above the horizon). The expression nocturnal arc refers to the distance, expressed in degrees and minutes of a circle, that a planet traverses between its setting in the west and its rising in the east. Classical astrology also classified signs as diurnal (the masculine signs) and nocturnal (the feminine signs). Contemporary astrologers no longer use the expression nocturnal sign.


Bach, Eleanor. Astrology from A to Z: An Illustrated Source Book. New York: Philosophical Library, 1990.

Brau, Jean-Louis, Helen Weaver, and Allan Edmands. Larousse Encyclopedia of Astrology. New York: New American Library, 1980.

The Astrology Book, Second Edition © 2003 Visible Ink Press®. All rights reserved.


Active during the nighttime.
(science and technology)
Occurring during the nighttime.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
Paroxysmal Nocturnal Hemoglobinuria (PNH) Treatment Country Outlook (Revenue, USD Million, 2017 - 2025)
The aye-aye is an endangered nocturnal primate native to Madagascar, with fewer than 60 in captivity around the world.
The Anambra State police command on Friday said it has arrested one suspected members of a cult group during their nocturnal meeting on how to launch an attack on their perceived rivals in the state.
Summary: Ahmedabad (Gujarat) [India] Apr 12, (ANI): Kankaria, India's first nocturnal zoo, records over Rs 3 crore yearly income.
Srinagar -- In occupied Kashmir, Indian police and troops have arrested five youth during nocturnal raids in Budgam district.
Achillion Pharmaceuticals announced achievement of enrollment in their ACH-4471 Phase 2 paroxysmal nocturnal hemoglobinuria trial in combination with eculizumab.
Unless you have a condition known as nocturnal lagophthalmos where you can't completely close your eyes while you are asleep.
United States Food and Drug Administration (USFDA) has approved Ultomiris (ravulizumab) injection intended for the treatment of adult patients with paroxysmal nocturnal hemoglobinuria, it was reported yesterday.
Nocturnal Animals, owned by Alex Claridge, who is also chef owner of The Wilderness restaurant in the Jewellery Quarter, has been the most anticipated opening of the year.
Thunderstorms that form with no nearby surface boundary account for ~25% of all nocturnal convection initiation (CI) events over the Great Plains.
Request for Sample Report @ On the basis of indication type, the market is segmented into mixed nocturia, low nocturnal bladder capacity, nocturnal polyuria and global polyuria.