Green’s Dictionary of Slang

canvas n.

1. the human skin.

[UK]C. Hindley Life and Adventures of a Cheap Jack 229: She is a prime girl; she is A. Number one, copper-bottomed [...] she is full-rigged, and carries a lot of canvas.

2. (US tramp) clothing.

[US]Sun (NY) 21 May 28/1: ‘If I make fifty or sixty bills dis winter I’ll buy myself some [...] new canvas (clothes)’.

3. (US Und.) a strait-jacket.

[US]Monteleone Criminal Sl. (rev. edn).

In compounds

canvasback (n.)

(Aus.) a second-rate boxer who spends most of his time lying on the canvas .

[Aus]B. Matthews Intractable [ebook] ‘You can’t take a punch. You’re a fucking canvas back’.