slater

noun3

1. •
   (Australia, Scotland) Any terrestrial isopod crustacean of the genus Porcellio and allied genera; a woodlouse.
2. •
   One who lays slates, or whose occupation is to slate buildings.
3. •
   A harsh critic; one who slates or denigrates something.

   • Plain speaking, now and then, is very necessary. The author will call the critic a “blackguard slater," of course, but he need not be a blackguard. Ferocity of language only hurts his effect. — 1901