Similar word to permission:

acceptance, acknowledgment, acquiescence, admission, agreement, allowance, approbation, approval, assent, avowal, canonization, carte blanche, concession, concurrence, condonance, condonation, dispensation, empowerment, endorsement, freedom, imprimatur, indulgence, leave, letting, liberty, license, okay, permit, privilege, promise, recognition, rubber stamp, sanctification, sanction, stamp of approval, sufferance, tolerance, toleration, verification, warrant