Synonyms for Coupling (same or very similar meaning)
WordNet sense 1 (a connection (like a clamp or vise) between two things so they move together):
yoke
WordNet sense 2 (a mechanical device that serves to connect the ends of adjacent objects):
coupler
WordNet sense 3 (the act of pairing a male and female for reproductive purposes):
conjugation, mating, union, pairing, sexual union
From the ODE community, based on WordNet
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