Freebase(0.00 / 0 votes)Rate this definition: Tongue. The tongue is a muscular hydrostat on the floors of the mouths of most vertebrates which manipulates food for mastication. It is the primary organ of taste, as much of the upper surface of the tongue is covered in papillae and taste buds.
1. eugenics-the study of methods of improving genetic qualities by selective breeding (especially as applied to human mating). bioscience, life science-any of the branches of natural science dealing with the structure and behavior of living organisms.
Definition of narcissism. 1  1 : egoism, egocentrism â¦ up until my late 30's I lived in a state of utterly monstrous narcissism and self-absorption â¦ â Frank Conroy. 2  2 : love of or sexual desire for one's own body His wife complained that she couldn't compete with her husband's narcissism.