Green’s Dictionary of Slang

to break wind loudly; occas. also of the vagina, to make a similar noise during intercourse; thus trumping n. and adj.

1660		Wandring Whore III 4: Oh! how sweet would be the death, as once a seeming-holy sister said when a long t[arsed] chyrurgion made her trump and trump again and again.
1700		N. Ward ‘A Step to Stir-Bitch-Fair’ in Writings (1704) 263: Some wild Scholars [...] had the usual Recourse thither, kist the Wenches till they Farted again, from whence, as some Sages conjecture, in process of Time, it gain’d the name of Trumping-Town.
1709		N. Ward Compleat and Humorous Account of Remarkable Clubs (1756) 33: They drank the King’s Health, and then there was such Trumping about to signalize their loyalty, that the Victualler was obliged to burn Rosemary in his Kitchen.
1772		Bridges Burlesque Homer (3rd edn) 456: Bawbling a song to suit the case, / To which her bum plaid thorough-bass / But made such thund’ring as she trump’d, / Both ajax and achilles jump’d.
c.1825		Friar and Boy 20: But straight her b-m did trump / And set all in a laughter.
1989		Viz June–July 24: Your mother expected you would stuff yourself with a feast of trumping time bombs.