Silence, hold your tongue. TACE is Latin for a candle; a jocular admonition to be silent on any subject.
Definition taken from The 1811 Dictionary of the Vulgar Tongue, originally by Francis Grose.
Tabby * TackleNathan Bailey's 1736 Dictionary of canting and thieving slang
John S. Farmer's collection of canting songs and slang rhymes