Green’s Dictionary of Slang

1. (US Und.) an act of robbery; a robber.

1823		(ref. to late 18C) Byron note to Don Juan Canto XI stanza 19: The following is a stanza of a song which was very popular, at least in my early days [...] ‘If you at the spellken can’t hustle / You’ll be hobbled in making a clout’.
1929		E. Booth Stealing Through Life 296: This is a fast clout.
1950		Goldin et al. DAUL 46/1: Clout, n. A theft, especially from markets or shops; the act of shoplifting.
1962		D. Dempsey ‘Lang. of Traffic Policemen’ in AS XXXVII:4 267: car clout, n. One who burglarizes automobiles.
1976		R. Daley To Kill a Cop 95: This wasn’t an ordinary car clout. I mean the thief didn’t just grab a car parked on the street.
1993		Lerner et al. Dict. of Today’s Words 29: Car clout – a car break-in.

2. (US) a thief, e,g. a pickpocket or shoplifter.

1937		B. Dai Opium Addiction in Chicago 196: Clout, the. Shoplifters.
1937		‘Boxcar Bertha’ Sister of the Road (1975) 306: shop-lifter, booster, derrick or clout. The girl who steals things from stores.
1949		Monteleone Criminal Sl. (rev. edn) 53: clout [...] a thief.