Green’s Dictionary of Slang

1. the penis, thus dibble in, to enter a woman.

c.1796		Burns ‘Brose an’ Butter’ Merry Muses of Caledonia (1965) 72: Hey for the gardener lad, To gully awa wi his dibble.
1870		Cythera’s Hymnal 26: He dibbled in with might and main his root, root, root.
1890–1904		Farmer & Henley Sl. and Its Analogues.
1922		Joyce Ulysses 485: Spanish fly in his fly or mustard plaster on his dibble.

2. (US campus) a fool, a social inadequate.

1966

Current Sl. I:1 2/1: Dibble A backward person.