Mawson, C.O.S., ed. (1870–1938). Roget’s International Thesaurus. 1922.
Class I. Words Expressing Abstract RelationsSection V. Number
2. Determinate Number
89. Duality
two, deuce, couple, couplet, both, twain, brace, pair, cheeks, twins, Castor and Pollux, gemini, Siamese twins; fellows; yoke, conjugation; dispermy, doublets, dyad, duad, twosome [rare], distich, span.
COUPLED &c. v.; conjugate.
BOTH, both the one and the other.