"small hanging piece from a garment," c.1400, perhaps from a Scandinavian source (cf. Norwegian tagg "point, prong, barb," Swedish tagg "prickle, thorn," Middle Low German tagge "branch, twig, spike"); cognate with tack (n.1). Meaning "label" is first recorded 1835; sense of "automobile license plate" is recorded from 1935, originally underworld slang. Meaning "an epithet, popular designation" is recorded from 1961, hence slang verb meaning "to write graffiti in public places" (1990).
"children's game," 1738, perhaps a variation of Scot. tig "touch, tap" (1721), probably an alteration of Middle English tek "touch, tap" (see tick (2)).
"to furnish with a tag," mid-15c., from tag (n.1). Related: Tagged; tagging. To tag along is first recorded 1900.
in the baseball sense, 1907, from tag (n.2); the adjective in the pro-wrestling sense is recorded from 1955.
A strip of leather, paper, metal, or plastic attached to something or hung from a wearer's neck to identify, classify, or label.
A small outgrowth or polyp.
To label, identify, or recognize with or as if with a tag.
To incorporate into a compound a readily detected substance making the compound detectable so that its metabolic or chemical history may be followed.
[final sense fr the fact that many such graffiti are the names, or tags, of the painter]