From today’s OED Word of the Day:

knitting, vbl. n. […]

c. A girl or girls. slang.

1943 C. H. WARD-JACKSON Piece of Cake 39 Knitting, girl or girls. 1946 J. IRVING Royal Navalese 104 Knitting, girls in the plural. The singular of this is ‘A Piece of Knitting’. 1962 GRANVILLE Dict. Sailors’ Slang 68/2 Knitting, girl friend or girls collectively.

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