affinity

favor, one-sidedness, partisanship, prejudice

endowment, faculty, flair, genius, gift, knack, talent

addiction, appetite, fancy, fondness, like, liking, preference, taste

forte, speciality, specialty

convention, custom, habit, pattern, practice (also practise), routine, trick, way, wont

eccentricity, idiosyncrasy, kink, oddity, peculiarity, quirk, singularity

correlation, interrelation

materiality, pertinence, relevance

bond, link, tie

affiliation, alliance, union

identicalness, sameness

alikeness, community, likeness, resemblance, similarity

accordance, agreement, conformity, congruity, correspondence