What does "lincoln tunnel" mean in gay sex?

A term to describe a person's anus, that is considered to be loose, or not very tight.

Definition

Referenced to any large wide open venue, to denote a rather large opening.

A term to describe a person's anus, that is considered to be loose, or not very tight, upon insertion of one's penis. Describing the immediate effect of one's anus opening, after being pummelled by a rather over sized dick, or sex toy.