to deflower.

dock is not a synonym for wharf although it is often used as such. The dock is water, the wharf is the abutting land or landing.

Dock is by many persons used to mean a wharf or pier; thus: “He fell off the dock and was drowned.... A man might fall into a dock ; but to say that he fell off a dock is no better than to say that he fell off a hole.”--R. G. WHITE, Words and Their Uses, ch. 5. p. 107.

To dock: To lie with a woman. The cull docked the dell all the darkmans; the fellow laid with the wench all night. Docked smack smooth; one who has suffered an amputation of his penis from a venereal complaint. He must go into dock; a sea phrase, signifying that the person spoken of must undergo a salivation. Docking is also a punishment inflicted by sailors on the prostitutes who have infected them with the venereal disease; it consists in cutting off all their clothes, petticoats, shift and all, close to their stays, and then turning them into the street.