- Lavoesium La*v[oe]"si*um, n. [NL., fr. Lavoisier, the celebrated French chemist.] (Chem.) A supposed new metallic element, which was said to have been discovered in pyrites, and some other minerals, and to be of a silver-white color, and malleable. It is not currently (1998) a recognized element. [1913 Webster +PJC]
The Collaborative International Dictionary of English. 2000.