Green’s Dictionary of Slang

1. (UK black) a prostitute.

1935		in Cassidy & LePage Dict. Jam. Eng. (1980).
1977		D. Powis Signs of Crime 174: Blue foot Prostitute (used in hippy communes and probably of West Indian origin).
1999		(con. 1979–80) A. Wheatle Brixton Rock (2004) 76: My friend told me you danced with the blue-foot for all friggin night.
2001		(con. 1981) A. Wheatle East of Acre Lane 122: Nuff leggo beast an’ blue foot were always der [...] dem whores who operate from Bedford Hill.
2005		(con. 1951) A. Wheatle Island Songs (2006) 843: Yuh t’ink me coulda ever breed pickney before me get married? Yuh t’ink me ah bluefoot?

2. (W.I.) a person of mixed race, esp. one who is despised; also as adj.

1929		M. Beckwith Black Roadways 83: Get up, you brute, blue-foot brute!
1996		Allsopp Dict. Carib. Eng. Usage.