Swinging Part of a Clock
This page is the CodyCross answer for the clue below from Tracking Time, Group 1060, Puzzle 1 (Digital Clock).
Question is: Swinging Part of a Clock
and the answer is: PENDULUM
Word Meaning:
PENDULUM — (clocks, mechanics) A body suspended from a fixed support so that it swings freely back and forth under the influence of gravity, commonly used to regulate various devices such as clocks.
Definitions from Wiktionary.