dusters, n. — Green’s Dictionary of Slang

dusters n.

[? boastful image of testicles that hang so low as to ‘dust’ the floor]

(orig. milit.) the testicles.

1961		in Randolph & Legman Ozark Folksongs and Folklore (1992) I 403: If I cotch him here wid me Jinny anymore, / I’ll tattoo his dusters, an’ he won’t fuck anymore.
1972		B. Rodgers Queens’ Vernacular.
1980		Maledicta IV:2 (Winter) 195: [Testicles] are commonly called balls or ballocks, stones or dusters, apples or nuts.