Green’s Dictionary of Slang

1. ‘Cutting out the backs of coaches and robbing the seats’ (Grose 1788); thus impudent stealer.

1708		J. Hall Memoirs (1714) 6: Impudent Stealers, Such as cut out the Backs of Coaches, and take Things out of them.
c.1786		Grose Classical Dict. of the Vulgar Tongue ms. additions n.p.: Impudent Stealing, Cuting [sic] out the bacs of coaches & robbing the seats.
1788, 1796		Grose Classical Dict. of the Vulgar Tongue (2nd, 3rd edn).
1811		Lex. Balatronicum [as cit. 1788].
1862		E. de la Bédollière Londres et les Anglais 315/1: impudent stealing, vol du siège de derrière d’une voiture pendant qu’elle est en marche.

2. (US, also impudent) cutting off the tails of a man’s coat.

1859

Matsell Vocabulum 44: Impudent To cut the tails of a man’s coat.