DIURNAL
diurnal
(adjective) of or belonging to or active during the day; “diurnal animals are active during the day”; “diurnal flowers are open during the day and closed at night”; “diurnal and nocturnal offices”
diurnal
(adjective) having a daily cycle or occurring every day; “diurnal rotation of the heavens”
Source: WordNet® 3.1
Etymology
Adjective
diurnal (comparative more diurnal, superlative most diurnal)
Happening or occurring during daylight, or primarily active during that time.
(botany) Said of a flower open, or releasing its perfume during daylight hours, but not at night.
Having a daily cycle that is completed every 24 hours, usually referring to tasks, processes, tides, or sunrise to sunset; circadian.
(uncommon) Done once every day; daily, quotidian.
(archaic) Published daily.
Synonyms
• (having a daily cycle): circadian (biology)
Antonyms
• (happening or active during the day): nocturnal, nightly
• (active or open during the day): nocturnal
Coordinate terms
• (active or open during the day): crepuscular
Noun
diurnal (plural diurnals)
A flower that opens only in the day.
(Catholicism) A book containing canonical offices performed during the day, hence not matins.
(archaic) A diary or journal.
(archaic) A daily news publication.
Source: Wiktionary
Di*ur"nal, a. Etym: [L. diurnalis, fr. dies day. See Deity, and cf.
Journal.]
1. Relating to the daytime; belonging to the period of daylight,
distinguished from the night; -- opposed to Ant: nocturnal; as,
diurnal heat; diurnal hours.
2. Daily; recurring every day; performed in a day; going through its
changes in a day; constituting the measure of a day; as, a diurnal
fever; a diurnal task; diurnal aberration, or diurnal parallax; the
diurnal revolution of the earth.
Ere twice the horses of the sun shall bring Their fiery torcher his
diurnal ring. Shak.
3. (Bot.)
Definition: Opening during the day, and closing at night; -- said of
flowers or leaves.
4. (Zoöl.)
Definition: Active by day; -- applied especially to the eagles and hawks
among raptorial birds, and to butterflies (Diurna) among insects.
Diurnal aberration (Anat.), the aberration of light arising from the
effect of the earth's rotation upon the apparent direction of motion
of light.
– Diurnal arc, the arc described by the sun during the daytime or
while above the horizon; hence, the arc described by the moon or a
star from rising to setting.
– Diurnal circle, the apparent circle described by a celestial body
in consequence of the earth's rotation.
– Diurnal motion of the earth, the motion of the earth upon its
axis which is described in twentyfour hours.
– Diurnal motion of a heavenly body, that apparent motion of the
heavenly body which is due to the earth's diurnal motion.
– Diurnal parallax. See under Parallax.
– Diurnal revolution of a planet, the motion of the planet upon its
own axis which constitutes one complete revolution.
Syn.
– See Daily.
Di*ur"nal, n. Etym: [Cf. F. diurnal a prayerbook. See Diurnal, a.]
1. A daybook; a journal. [Obs.] Tatler.
2. (R. C. Ch.)
Definition: A small volume containing the daily service for the "little
hours," viz., prime, tierce, sext, nones, vespers, and compline.
3. (Zoöl.)
Definition: A diurnal bird or insect.
Source: Webster’s Unabridged Dictionary 1913 Edition