grader

noun4

1. •
   A machine used to sort food by size or quality.
2. •
   [in compounds] One who belongs to a certain grade at school.
3. •
   One who grades, or that by means of which grading is done or facilitated.
4. •
   A machine used in road maintenance, construction, and mining for leveling large surfaces.

   • The blade-grader is a long steel-framed carriage under which is fixed a steel blade capable of being tilted at various angles: its principal use is in trimming cutting-slopes. — 1943