A chameleon is a reptile known for its ability to seemingly change color. They have "pigment granules" controlled by their brain's central nervous system. The Physics of the Buffyverse tells this regarding their color changing ability:

"They can do this because they have several layers of cells...Under the transparent outer skin are two cell layers containing red and yellow pigments; under these are cell layers that reflect blue and white, supported by an even deeper layer of brown melanin" (Ouellette).

Before going further, since this is a blog and not a news report, I noticed that Jennifer Ouellette's last name reminds me of the word oubliette which means dungeon and was also a 1914 silent film starring Lon Chaney.

I was also thinking about the components of the word chameleon, since the ch is pronounced as k. The origin of the word is this:

"Word Origin & History. chameleon. mid-14c., from O.Fr. chaméléon, from L. chamaeleon, from Gk. khamaileon, from khamai "on the ground" (also "dwarf")" (http://dictionary.reference.com/browse/chameleon).

Chameleons can range in color from bright parrot-like to drab browns. They can vary in size from very small to quite large, such as the Malagasy Giant Chameleon found in Madagascar. Its scientific name is Furcifer oustaleti, furcifer meaning forked, referring to its feet, not its tongue.

Chameleon can also refer to a person whose personality seems to change depending on circumstances and often refers to a "fair weather friend".

I don't think I've ever had contact with a live chameleon, but certainly everyone, even me, has had some experience with the metaphorical chameleon.