"signal calling soldiers or sailors to quarters at night," 1680s, earlier tap-to (1640s), from Dutch taptoe, from tap "faucet of a cask" (see tap (n.1)) + toe "shut, to," from Proto-Germanic *to (see to (prep.)). "So called because police formerly visited taverns in the evening to shut off the taps of casks" [Barnhart]. In 17c. Dutch the phrase apparently was used with a transferred or figurative sense "say no more." In English, transferred sense of "drumbeat" is recorded from 1755. Hence, Devil's tattoo "action of idly drumming fingers in irritation or impatience" (1803).
"pigment design in skin," 1769 (noun and verb, both first attested in writing of Capt. Cook), from a Polynesian noun (such as Tahitian and Samoan tatau, Marquesan tatu "puncture, mark made on skin"). Century Dictionary (1902) describes them as found on sailors and uncivilized people or as a sentence of punishment. Earlier names in English included Jerusalem cross (1690s) in reference to tattoos on the arms of pilgrims to the Holy Land, also Jerusalem letters (1760).
"mark the skin with pigment," 1769, tattow, from tattoo (n.2). Related: Tattooed; tattooing. Thackeray has tattooage.