crime against nature

Definition from Nolo’s Plain-English Law Dictionary

An archaic term used to describe sexual practices deemed deviant or not natural by a legislature or a court. Examples range from bestiality (intercourse between a human and an animal) to necrophilia (intercourse with a dead body). Few states still have "crime against nature" statutes on the books, and any that still include consensual sexual acts, such as sodomy, between adults are unconstitutional under a 2003 United States Supreme Court decision, Lawrence v. Texas.

Definition provided by Nolo’s Plain-English Law Dictionary.