Green’s Dictionary of Slang

pushing-block n.

[push v. (1); SE block suggests the woman's supposedly passive role in intercourse]

(Irish) a female companion.

[Ire] ‘Kilmainham Minit’ in A. Carpenter Verse in Eng. in 18C Ireland (1998) 436: His Pushing-block pissey came in, / From tipping de Scragboy Dusting; / Her Stuff-shop was up to the Chin, / Like a cram’d Fowl wid Tenderness busting.