to time with a stopwatch [v CLOCKED, CLOCKING, CLOCKS]
to begin work, esp. by punching a time clock
to end work, esp. by punching a time clock
to use up as much game time as possible when one is winning, as to protect a lead in basketball, ice hockey, or football
to postpone an official or legal deadline by ceasing to count the hours that elapse, as when a new union contract must be agreed upon before an old contract runs out