pledge

bail, bond

deposit, down payment, earnest, handsel

surety, warranty

assurance, oath, promise, troth, word

commitment, compact, contract, covenant

recognizance

appointment, arrangement, commitment, engagement, obligation

agreement, compact, contract, covenant

assurance, guarantee, guaranty, undertaking

bail, bond, deposit, gage, pawn, security, token, warranty

affiance, betroth, plight, promise, swear, vow

contract, enlist, enroll (also enrol), sign on, sign up

overcommit

deposit, mortgage

bond

affiance, betroth, plight, troth

accede, agree, assent, consent

contract, engage, ensure, guarantee, undertake

affirm, assert, aver, avouch, avow, declare, insist, warrant