Green’s Dictionary of Slang

Andy McGinn n.

the chin.

1934		Detective Fiction Weekly (US) 21 Apr. in DU (1949).
1944		Maurer & Baker ‘“Aus.” Rhyming Argot’ in AS XIX:3 190/1: Andy McGinn, chin.
1960		J. Franklyn Dict. of Rhy. Sl.
1960		(con. 1950-1960) R.A. Freeman Dict. Inmate Sl. (Walla Walla, WA) 3: Andy Maginn – chin.
2002		Rick Walton Sl. to Eng. Dict. 🌐 Andy McGinn – chin.