Etymology
From Middle English scluttish, slottesche, slottysch, sluttissche, sluttissh; equivalent to slut + -ish.
Adjective
sluttish (comparative more sluttish, superlative most sluttish)
- (vulgar) Like a slut; sexually promiscuous.
1988, Alan Hollinghurst, The Swimming-Pool Library, paperback edition, London: Penguin Books, →ISBN, page 2:His name was perhaps the least likely ever to have been young: it evoked for me the sunless complexion, unaired suiting, steel-rimmed glasses of a ledger clerk in a vanished age. Or had done so, before I found my beautiful, cocky, sluttish Arthur—an Arthur it was impossible to imagine old.
- (chiefly dated) Dirty or untidy; disorderly.
1815 February 24, [Walter Scott], Guy Mannering; or, The Astrologer. […], volume (please specify |volume=I to III), Edinburgh: […] James Ballantyne and Co. for Longman, Hurst, Rees, Orme, and Brown, […]; and Archibald Constable and Co., […], →OCLC:[…] an air of liberal, though sluttish, plenty, indicated the wealthy farmer.
1996 February 7, Helen Fielding, “Bridget Jones's Diary”, in The Independent, London, retrieved 3 March 2009:"Check plates and cutlery for tell-tale signs of sluttish washing up […] "