The Collaborative International Dictionary
Cyatholith
Cyatholith \Cy*ath"olith\ (s?-?th"?-l?th), n. [Gr. ky`aqos a cup + -lith.] (Biol.) A kind of coccolith, which in shape resembles a minute cup widened at the top, and varies in size from 1/6000 to 1/8000 of an inch.
Wiktionary
cyatholith
n. (context biology English) A kind of coccolith resembling a minute cup widened at the top.