sublingua

Century Dictionary and Cyclopedia

1. n. A process of the mucous membrane of the floor of the mouth developed between the tip of the tongue and the symphysis of the lower jaw of some animals, as lemurs: it may acquire considerable size, and become denticulated or pectinated.

Wiktionary

1. n. anatomy A muscular secondary tongue found below the primary tongue in prosimian primates.

GNU Webster's 1913

1. n. (Anat.) A process or fold below the tongue in some animals.