Fellowship
Friendship, fellowship, association, alliance, attachment, link, union, relationship, partnership, affiliation, coalition, tie, connection, and nexus.
Pledge
Promise, vow, oath, word of honour, guarantee, agreement, engagement, obligation, pact, bargain, settlement, compact, concordat, bail, troth, pledge, avowal, word, solemn word, assurance, understanding, commitment, contract, transaction, deal, covenant, treaty, accord, and parole.