a stopwatch is used for measuring time
stop_watch is way_to_measure_quick_time. timepiece is measuring_instrument. stopwatch is timer. wristwatch is way_to_tell_time. wristwatch is device_for_telling_time. watches is devices_for_measuring_time. time is measurement. stopwatch is old_device_for_measuring_time. caliper is distance_measuring_device. watch is mechanical_means_of_measuring_time.