Con‐trol″ler (?), n. [From control, v. t.: cf. F. contrôleur.] 1. One who, or that which, controls or restraines; one who has power or authority to regulate or control; one who governs.
The great controller of our fate
Deigned to be man, and lived in low estate.
Dryden.
2. An officer appointed to keep a counter register of accounts, or to examine, rectify, or verify accounts. [More commonly written controller.]
3. (Naut.) An iron block, usually bolted to a ship's deck, for controlling the running out of a chain cable. The links of the cable tend to drop into hollows in the block, and thus hold fast until disengaged.