'mark off' definitions:

Definition of 'mark off'

(from WordNet)
verb
Set boundaries to and delimit; "mark out the territory" [syn: mark off, mark out]
verb
Put a check mark on or near or next to; "Please check each name on the list"; "tick off the items"; "mark off the units" [syn: check, check off, mark, mark off, tick off, tick]

Synonyms of 'mark off'

From: Moby Thesaurus