Etimology
From Middle English houre, hour, oure, from Anglo-Norman houre, from Old French houre, (h)ore, from Latin hōra (“hour”), from Ancient Greek ὥρα (hṓra, “any time or period, whether of the year, month, or day”), from Proto-Indo-European *yóh₁r̥ (“year, season”). Akin to Old English ġēar (“year”). Doublet of hora and year. Partly displaced native Old English tīd (“time, hour”), whence Modern English tide.
noun
hour (plural hours)
A unit of time of one twenty-fourth of a day (sixty minutes).
A season, moment, or time.
(poetic) The time.
(military, in the plural) Used after a two-digit hour and a two-digit minute to indicate time.
(Christianity, in the plural) The set times of prayer, the canonical hours, the offices or services prescribed for these, or a book containing them.
(chiefly US) A distance that can be traveled in one hour.
Examples
I spent an hour at lunch.
During the whole time of his abode in the university he generally spent thirteen hours of the day in study; by which assiduity besides an exact dispatch of the whole course of philosophy, he read over in a manner all classic authors that are extant […]
It is never possible to settle down to the ordinary routine of life at sea until the screw begins to revolve. There is an hour or two, after the passengers have embarked, which is disquieting and fussy.
[Isaac Newton] was obsessed with alchemy. He spent hours copying alchemical recipes and trying to replicate them in his laboratory. He believed that the Bible contained numerological codes. The truth is that Newton was very much a product of his time.
From childhood's hour I have not been / As others were; I have not seen / As others saw; I could not bring / My passions from a common spring.
Now will be a good hour to show you Milly Erne's grave.
The hour grows late and I must go home.
By 1300 hours the position was fairly clear.
This place is an hour away from where I live.
Related words
synonyms
(period of sixty minutes, a season or moment): stound (obsolete); microcentury (humorous approximation)