chameleon (n.)

lizard-like reptile notable for its ability to change color, mid-14c., camelion, from Old French caméléon, from Latin chamaeleon, from Greek khamaileon "the chameleon," from khamai "on the ground" (also "dwarf"), akin to chthon "earth" (from PIE root *dhghem- "earth") + leon "lion" (see lion).

Perhaps the large head-crest on some species was thought to resemble a lion's mane. Greek khamalos meant "on the ground, creeping," also "low, trifling, diminutive." The classical -h- was restored in English early 18c. Figurative sense of "variable person" is 1580s. It formerly was supposed to live on air (as in "Hamlet" III.ii.98). The constellation was one of the 11 added to Ptolemy's list in the 1610s by Flemish cartographer Petrus Plancius (1552-1622) after Europeans began to explore the Southern Hemisphere.