Green’s Dictionary of Slang

(orig. US) a bartender, esp. as a mixer of cocktails; thus mixology, mixing cocktails.

1856		Knickerbocker (N.Y.) June 615: Who the h—l ever heard of a man’s [...] calling the barkeeper a mixologist of tipicular fixins?
1870		W.F. Rae Westward by Rail xv. 201: The most delicate fancy drinks are compounded by skilful mixologists in a style that captivates the public.
1900		Colored American (DC) 10 Nov. 3/1: The Mixologist Club is made up principally of the very useful gentlemen who tickle the popular palate with artistic combinations of the ‘fluid that cheers’.
1907		Sun. Times (Perth) 12 May 4/7: The slick mixiologist rolled off a few of the best-known drinks.
1908		W.G. Davenport Butte and Montana beneath the X-Ray 45: Brandy and cigarettes were furnished by an expert mixologist from the Thornton Hotel [DA].
1912		Day Book (Chicago) 26 June 6/1: Every footloose bar keep in Washington has been huried to baltimore [...] B&O trains are crowded with mixologists.
1922		S. Lewis Babbitt (1974) 169: Miriam here is the best little mixologist in the Stati Unidos.
1939		Afro-American (Baltimore, MD) 7 Jan. 9/4: The Riley and mex firm of mixologists at Wendell’s vilma tavern.
1948		New Yorker 6 Nov. 62/3: In 1901, the Police Gazette, then at the apex of its educational influence, attempted to revive and glorify mixologist, but the effort failed miserably [DA].
1999		B. Emmons Book of Gins and Vodkas 63: The difference between a bartender and a mixologist can be confusing [...] The bartender is more of a people type of guy and a mixologist has acquired the facility for making drinks very fast.
2004		M. Hellmich Sangria 6: The key character of sangria is in its adventuresome flexibility, enabling endless ingredient variations depending on [...] the mixologist’s preferences.