dual

American  

[doo-uhl, dyoo-] / ˈdu əl, ˈdyu- /

adjective

1. of, relating to, or noting two.

2. composed or consisting of two people, items, parts, etc., together; twofold; double.

   dual ownership;

   dual controls on a plane.

3. having a twofold, or double, character or nature.

4. Grammar. being or pertaining to a member of the category of number, as in Old English, Old Russian, or Arabic, that denotes two of the things in question.

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noun

Grammar.

1. the dual number.

2. a form in the dual, as Old English git “you two,” as contrasted with ge “you” referring to three or more.

dual British  

/ ˈdjuːəl /

adjective

1. relating to or denoting two

2. twofold; double

3. (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. maths 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

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noun

1. grammar

   1. the dual number

   2. a dual form of a word

verb

1. (tr) to make (a road) into a dual carriageway

Other Word Forms

• dually adverb

Etymology

Origin of dual

First recorded in 1535–45; from Latin duālis “containing two, relating to a pair,” equivalent to du(o) two + -ālis -al ¹

Example Sentences

The six Italians killed in the disaster included two girls aged 15 and 16, three boys aged 16, and a 16-year-old Italian-Emirati dual national.

From Barron's

They included 21 Swiss nationals, and one French-Swiss dual national, aged 14 to 31.

From Barron's

If you are keen to apply to get on the course, French citizenship is an essential requirement, although some dual citizens are accepted.

From BBC

Baldy has outdoors enthusiasts explaining, in online forums and to reporters, the dual nature of the mountain’s conditions.

From Los Angeles Times

Here was someone else connected to America, she assumed, probably another like-minded dual citizen or expat.

From The Wall Street Journal