Green’s Dictionary of Slang

1. sexual intercourse, often adultery; usu. as dance the hornpipe.

1590		Tarltons Newes 25: Amorous [Stephano] the chief gallant of all the parish for dancing of a Lincolnshire hornepipe in the Churchyard on sondaies.
1607		Dekker & Webster Northward Hoe I iii: Oh Maister Maybery! before your Seruant to daunce a Lancashire Horne-pipe.
c.1621		Middleton Women Beware Women III ii: I’ll venture but a hornpipe with her, guardianer, Or some such married man’s dance [...] Cuckolds dance the hornpipe.
1629		Massinger Picture III vi: [She] danc’d to his hornpipe or there are liars abroad.
1630		J. Taylor ‘A Bawd’ in Works (1869) II 96: [She is an] old dogge at a hornepipe, her chiefest instrument is a Sackbut.
c.1700		London-Bawd (1705) 3: [She is] a great Practitioner in Prick-Song, but she is most expert at a Horn-Pipe.
a.1749		Robertson of Struan ‘A la mode de France’ Poems (1752) 269: She ne’er to a Horn-pipe would frisk any more.

2. a penis.

1658		F. Osborne Historical Memoires 89: Many a Horne-pipe he tun’d to his Phyllis, And sweetly sung Walsingham to’s Amaryllis. Till Atropos clapt him.
1772		Bridges Burlesque Homer (3rd edn) 243: [He] took the girl, and buckl’d to’t, / And fairly danc’d his hornpipe out.