encrustation
noun /ˌɪnkrʌˈsteɪʃn/
/ˌɪnkrʌˈsteɪʃn/
(also incrustation)
[uncountable, countable]- the process of forming a hard outer layer over something; the layer that is formedWord Originearly 17th cent. (originally as incrustation): from late Latin incrustatio(n-), from the verb incrustare, from in- ‘into’ + crusta ‘a crust’.