The state of being friends
association, companionship, alliance, confraternity, amity, concord, harmony, camaraderie, fellowship, comradeship, fraternization, attachment, bond, closeness, brotherhood, sisterhood, fraternity, comity, mutual regard, affinity, accord, league, pact, rapprochement (French), sympathy, rapport, understanding, agreement, compatibility, fellow feeling, intercourse, intimacy, familiarity, bonding.
Antonyms hatred*, hostility, enmity.
Friendly feeling
friendliness, good will, favor, devotion, regard, brotherly love, affection, fondness, consideration, esteem, good intentions, kindness, kindliness, amiability, amicability, neighborliness, sociability, loving-kindness, respect, attention, attentiveness, appreciation, tenderness, geniality, congeniality, heartiness, conviviality, affability, companionability, cordiality, good faith, confidence, attachment, loyalty, steadfastness, staunchness, responsiveness, understanding, warmth, sympathy, good humor, good nature, graciousness, benevolence, sincerity, generosity, chumminess*, clubbability*.
Antonyms hatred*, animosity, disfavor.