Definition of "keep time"

keep time

verb
third-person singular simple present keeps time, present participle keeping time, simple past and past participle kept time
1. To measure time.
2. To indicate the time correctly (of a timepiece).
3. To make any regular rhythmical movements at the same time with others.
4. To control the beat or rhythm of a song played by a music group.
5. To maintain a schedule set out in a timetable. (e.g. of a train)
  Quotations
  We never had a chance even to attempt to keep time. An empty stock train from Stewarts Lane was given the road just ahead of us, and from Grosvenor Bridge to Herne Hill we had the signals against us all the way.
  1959 April, P. Ransome-Wallis, “The Southern in Trouble on the Kent Coast”, in Trains Illustrated, London: Ian Allan Publishing, page 220