Balance wheel

1. A wheel which imparts regularity to the movements of any engine or machine; a fly wheel.
2. A wheel which regulates the beats or pulses of a watch or chronometer, answering to the pendulum of a clock; — often called simply a balance.
3. A ratchet-shaped scape wheel, which in some watches is acted upon by the axis of the balance wheel proper (in those watches called a balance).

The word meanings were obtained from OPTED(The Online Plain Text English Dictionary), which is based on “The Project Gutenberg Etext of Webster’s Unabridged Dictionary” which is in turn based on the 1913 US Webster’s Unabridged Dictionary (See Project Gutenburg), as a text file.