SIMMER

I. verb (~ed; ~ing) Etymology: alteration of English dialect simper, from Middle English simperen, of imitative origin Date: 1653 intransitive verb to stew gently below or just at the boiling point, 2. to be in a state of incipient development ; ferment , to be in inward turmoil ; seethe , transitive verb to cook slowly in a liquid just below the boiling point, II. noun Date: 1809 the state of ~ing