c.1500, ultimately imitative, also found in Middle Low German and Low German tuten "blow a horn." Related: Tooted; tooting. The noun is recorded from 1640s. Meaning "cocaine" is attested by 1977. Tooting as a strong affirmative (e.g. you're damned tootin') is attested from 1932, American English. Toots as a slang familiar form of address to a woman or girl is recorded from 1936, American English.
[the drinking sense is probably fr the image of someone tooting on a drinking horn, that is, holding a glass up as if it were a horn one were blowing; toot or tout, ''drink deeply, quaff,'' are attested fr the 1600s; narcotics sense probably related to honker, ''horn, nose,'' as something to be tooted]