■ noun
1》 a man's short, close-fitting padded jacket, worn from the 14th to the 17th century.
2》 chiefly technical a pair of similar things, e.g. lines in a spectrum.
↘a pair of words of the same derivation but different meanings, for example fashion and faction .
3》 ( ~s ) the same number on two dice thrown at once.
Origin
ME: from OFr., 'something folded', from double 'double'.