Green’s Dictionary of Slang

starkers adj.¹

nude.

1923		J. Manchon Le Slang 92: starko [...] = stark naked = starkers, tout nu.
1946		(con. 1912) B. Marshall George Brown’s Schooldays 16: Doing a bundle means getting dressed from starko in five minutes.
1963–74		B. Humphries Barry McKenzie [comic strip] in Complete Barry McKenzie (1988) 74: When I was drawing them starkers photos of her she looked as though she was trying to tell me something.
1974		(con. late 1940s) E. Thompson Tattoo (1977) 464: She was starkers.
1985		B. Humphries Traveller’s Tool 98: Old Niall was just sitting there on the bed, starkers.
1998		G. Burn Happy Like Murderers 87: There’s a big rug in front of the fire and she’s starkers lying on it.
2001		N. Griffiths Sheepshagger 94: I couldn’t’ve really given a fuck about Ianto sittin starkers in me house.
2004		IOL News (Western Cape) 12 Nov. 🌐 Before you know it, he is starkers.