c.1400, "a coloring, dye," from Latin tinctura "act of dyeing or tingeing," from tinctus "dye," past participle of tingere "to tinge, dye, soak in color," originally merely "to moisten, wet, soak," from PIE root *teng- "to soak" (cognates: Old High German dunkon "to soak," Greek tengein "to moisten"). Meaning "solution of medicine in a mixture of alcohol" is first recorded 1640s. The verb is recorded from 1610s. Related: Tinctured.