a timepiece that measures a time interval and signals its end
source: WordNet 3.0
(sports) an official who keeps track of the time elapsed
source: WordNet 3.0
a regulator that activates or deactivates a mechanism at set times
source: WordNet 3.0
A timekeeper; especially, a watch by which small intervals of time can be measured; a kind of stop watch. It is used for timing the speed of horses, machinery, etc.
source: Webster 1913
In electric ignition, an adjustable device for automatically timing the spark.