1. a spontaneous or natural liking or sympathy for someone or something: "he has an affinity for the music of Berlioz"Similarempathyrapportsympathyaccordharmonylike-mindednesscloseness tofellow feeling forunderstanding ofliking forfondness forinclination towardpartiality forpenchant forpredilection towardattraction towardinformal:chemistryrelationshipbondconnectionpropinquityOppositedislikeaversionantipathyblood relationship
▪ relationship, especially by marriage as opposed to blood ties.
▪ the degree to which a substance tends to combine with another:"the affinity of hemoglobin for oxygen"
Word OriginMiddle English (in the sense ‘relationship by marriage’): via Old French from Latin affinitas, from affinis ‘related’ (literally ‘bordering on’), from ad- ‘to’ + finis ‘border’.