(in the grammar of Old English, Ancient Greek, and certain other languages) denoting a form of a word indicating that exactly two referents are being referred to
4. mathematics, logic
(of structures or expressions) having the property that the interchange of certain pairs of terms, and usually the distribution of negation, yields equivalent structures or expressions
noun
5. grammar
a.
the dual number
b.
a dual form of a word
verbWord forms: duals, dualling or dualled
6. (transitive) British
to make (a road) into a dual carriageway
Derived forms
dually (ˈdually)
adverb
Word origin
C17: from Latin duālis concerning two, from duo two