Meaning of DUAL in English

I. adjective see: two Date: 1597 denoting reference to two, 2. consisting of two parts or elements or having two like parts ; double , having a double character or nature, ~ly adverb II. noun Date: 1650 the ~ number of a language, a linguistic form in the ~

Merriam Webster. Explanatory English dictionary Merriam Webster.      Толковый словарь английского языка Мерриам-Уэбстер.