Time beyond, or in excess of, a limit; esp., extra working time. [1913 Webster]
An extra period of time provided to play a game, beyond the end of the normal period allowed for the game, for the purpose of resolving a tie score; as, the team won in overtime. [PJC]

sudden death overtime an overtime{2} in which the first team to score wins the game; -- contrasted with normal overtime{2}, which is a fixed period of time during which either team may score as often as they can.

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OXFORD DICTIONARY

overtime, n. & adv.
--n.
1 the time during which a person works at a job in addition to the regular hours.
2 payment for this.
3 US Sport = extra time.
--adv. in addition to regular hours.

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THESAURUS

overtime

anchor watch, bit, day shift, dogwatch, full time, graveyard shift, half time, lobster trick, night shift, part time, relay, shift, split schedule, split shift, stint, sunrise watch, swing shift, time, tour, tour of duty, trick, turn, turn of work, watch, work shift

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