com·ma 
(kŏmə)
(kŏmə)n.
1. Grammar A punctuation mark ( , ) used to indicate a separation of ideas or of elements within the structure of a sentence.
2. A pause or separation; a caesura.
3. Any of several nymphalid butterflies of the genus Polygonia having wings with irregularly notched edges and a small comma-shaped marking on the underside of the hind wing.
[Latin, from Greek komma, piece cut off, short clause, from koptein, to cut.]