Synset
a hard outer layer that covers something
<noun.object>
crust
encrustation
incrustation
lexical pointers
derivationally related form
crusty
crust
lexical pointers
derivationally related form
incrust
incrust
lexical pointers
derivationally related form
encrust
encrust
semantic pointers
hypernym
cover, covering, natural covering
hyponym
tartar, calculus, tophus