glotto-, glot-, -glott (Greek: tongue; by extension, "speech, language").
They're skinny, thick, colored, sometimes sticky, occasionally nubbed flabs of flesh that dangle in the mouths of virtually every mammal, bird, reptile, fish and amphibian on Earth. Tongues, as we know these universal appendages, can zap prey, slurp water, groom a friendly shoulder, shovel food, taste, twist and enable their owners to make precise sounds.
The tongue presents a great anatomical puzzle. It is essentially solid muscle, but muscle by itself is usually useless. A muscle, that can perform work only by contracting, becomes useful when attached to something rigid like bone. When the muscle shortens, it pulls bones this way or that, providing the owner all sorts of mobility. For example, chameleons have a bone at the base of their tongues. Squeezing muscles against it makes the long tongue squirt out with extra force.
A tongue's muscles mingle at all sorts of angles, butting into each other head-on, stringing through a central core, curling around the outside like vines. For a given motion, one muscle group tenses and another one pulls the tensed group as if it were one. In a split second, groups trade roles so the tongue can flick the opposite way.
(International Wildlife, March-April, 1995), pp. 45-4