To be capable of; to permit. In this sense, "of" may be used after the verb, or may be omitted.
To allow to enter; to grant entrance (to), whether into a place, into the mind, or into consideration
To give warrant or allowance, to grant opportunity or permission (+ of).
To allow (someone) to enter a profession or to enjoy a privilege; to recognize as qualified for a franchise.
To concede as true; to acknowledge or assent to, as an allegation which it is impossible to deny (+ to).
To allow to enter a hospital or similar facility for treatment.
To make legally invalid.
To prevent from happening.
To make of no use or value; to cancel out.