[pum.ice] n [ME pomis, fr. MF, fr. L pumic-, pumex--more at foam] (15c): a volcanic glass full of cavities and very light in weight used esp. in powder form for smoothing and polishing -- pu.mi.ceous adj
PUMICE
Meaning of PUMICE in English
Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012