'rule out' definitions:

Definition of 'rule out'

From: WordNet
verb
Make impossible, especially beforehand [syn: preclude, rule out, close out]
verb
Include or exclude by determining judicially or in agreement with rules [syn: rule out, rule in]
verb
Dismiss from consideration or a contest; "John was ruled out as a possible suspect because he had a strong alibi"; "This possibility can be eliminated from our consideration" [syn: rule out, eliminate, winnow out, reject]