hour

noun \ˈau̇(-ə)r\

: one of the 24 equal parts of a day : 60 minutes

: the time shown on a clock or watch

: a particular time during the day

Full Definition of HOUR

: a time or office for daily liturgical devotion; especially : canonical hour

: the 24th part of a day : 60 minutes

a : the time of day reckoned in two 12-hour periods

b plural : the time reckoned in one 24-hour period from midnight to midnight using a 4-digit number of which the first two digits indicate the hour and the last two digits indicate the minute <in the military 4:30 p.m. is called 1630 hours>

a : a customary or particular time <lunch hour> <in our hour of need>; also : moment 1b <hero of the hour>

b plural : time of going to bed <keeps late hours>; also : time of working <banker's hours>

: an angular unit of right ascension equal to 15 degrees measured along the celestial equator

: the work done or distance traveled at normal rate in an hour <the city was two hours away>

a : a class session

b : credit hour, semester hour

— after hours

: after the regular quitting or closing time

See hour defined for English-language learners

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Origin of HOUR

Middle English, from Anglo-French ure, eure, from Late Latin & Latin; Late Latin hora canonical hour, from Latin, hour of the day, from Greek hōra — more at year

First Known Use: 13th century