OXFORD DICTIONARY
, adj., pron., & adv.
--adj. & pron. the two, not only one (both boys; both the boys; both of the boys; the boys are both here).
both ways = each way. have it both ways alternate between two incompatible points of view to suit the needs of the moment.
Widely used with of, esp. when followed by a pronoun (e.g. both of us) or a noun implying separate rather than collective consideration, e.g. both of the boys suggests each boy rather than the two together.
--adv. with equal truth in two cases (both the boy and his sister are here; are both here and hungry).
ME f. ON b{aacute}thir
THESAURUS
a deux, brace, couple, couplet, distich, double harness, doublet, duad, duet, duo, dyad, either, for two, match, mates, pair, set of two, span, team, tete-a-tete, the two, twain, two, twosome, yoke
ROGET THESAURUS
Duality
N
duality, dualism, duplicity, biplicity, biformity, polarity, two, deuce, couple, duet, brace, pair, cheeks, twins, Castor and Pollux, gemini, Siamese twins, fellows, yoke, conjugation, dispermy, doublets, dyad, span, two, twin, dual, dualistic, double, binary, binomial, twin, biparous, dyadic, conduplicate, duplex, biduous, binate, diphyletic, dispermic, unijugate, tete-a-tete, coupled, conjugate,
both,
both the one and the other.