Synonyms for Conjugation (same or very similar meaning)
WordNet sense 1 (the state of being joined together):
conjunction, junction, colligationWordNet sense 2 (the act of pairing a male and female for reproductive purposes):
coupling, mating, union, pairing, sexual unionWordNet sense 3 (the act of making or becoming a single unit):
unification, jointure, unitingFrom the ODE community, based on WordNetadd/edit