pumices is pumice's Plural Form

pumice

US [ˈpʌmɪs]
UK ['pʌmɪs]
  • n.轻石;浮岩;泡沫岩
  • v.用浮石磨
Plural Form:pumices  Singular:pumice stone  Plural Form:pumice stones  
n.
1.
轻石,浮石;浮岩;泡沫岩
v.
1.
用浮石磨,用轻石擦