written abbreviationhrTMCa unit for measuring time. There are 60 minutes in one hour, and 24 hours in one day.COLLOCATIONS COLLOCATIONS for an hour/two hours/three hours etc in an hour/in an hour's time (=when an hour has passed) an hour/two hours etc later an hour/two hours etc ago/earlier within hours (of something) (=only a few hours after something) half an houralso a half hour American English (a) quarter of an hour three quarters of an hour an hour's work (=work that it took you an hour to do) an hour's walk/drive miles/kilometres per hour (=used in speeds) £10/$5.50 etc an hour (=used to say how much someone is paid or how much you pay to use something) pay/charge by the hour (=pay or charge someone according to the number of hours it takes to do something)
There are flights to Boston every hour on the hour.
10/20 etc minutes before/after the hourAmerican English (=used on national radio or television in order to give the time without saying which hour it is, because the broadcast may be coming from a different time zone)
It's twelve minutes before the hour, and you're listening to Morning Edition on NPR.