clockkeeper
/ˈklɒkkiːpər/Definitions
1. noun
A person responsible for the maintenance and repair of a clock or clocks, especially in a large organization.
“The clockkeeper ensured that all office clocks were accurate and in working order.”
2. noun
A person who keeps track of the time for a group, especially in a sports context.
“The clockkeeper at the tennis tournament was responsible for calling out the time between points.”