noun
rare1The action or fact of coupling one person or thing to another; union, pairing, mating. Of persons. Frequently: marriage union.
2Of things.
3Woodworking Engineering
A component used to bind or brace together two other components of a structure; the structure so bound. Compare "tie".
Origin
Late 15th century; earliest use found in William Caxton (1415x24–1492), printer, merchant, and diplomat. From Middle French accouplement (of persons) coupling, sexual union, action of harnessing two animals together, pairing, union of marriage from accoupler + -ment.
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