24-hour clock UK /ˌtwɛntiˈfɔːɹˌaʊə ˈklɒk/US /ˌtwɛntiˈfɔɹˌaʊəɹ ˈklɔk/ noun1 •A timekeeping convention in which the 24 hours of the day are treated as a single period rather than two sets of 12 hours, with the result that midnight is indicated as 00:00 (or sometimes 24:00), and the hours from 1:00 to 11:00 p.m. as 13:00 to 23:00.Twenty-four hour clock time is gaining in favor. — 1893 forms24-hour clocks
