What is to make a hissing sound; as, a flatiron hot enough to siss when touched with a wet finger. [Colloq. U. S.; Local, Eng.] called?

siss — To make a hissing sound; as, a flatiron hot enough to siss when touched with a wet finger. [Colloq. U. S.; Local, Eng.]. (Webster's 1913.)

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