dual

[doo-uhl, dyoo-]

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.

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

/ 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

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

Word History and Origins

Origin of dual¹

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

Word History and Origins

Origin of dual¹

C17: from Latin duālis concerning two, from duo two

Example Sentences

They discovered that amyloid beta has a dual personality, depending on where it acts.

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The Fed’s dual mandate stipulates that it must pursue maximum employment and stable prices.

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Over the course of more than 20 novels, Mr. Banville has repeatedly granted his readers this dual perspective on a protagonist.

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Google’s dual role as a top cloud provider and leading developer of large language models also helps it maintain a competitive edge over rivals and provide a catalyst for Alphabet shares.

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The stock will be dual listed and shares are due to begin trading on the London Stock Exchange Thursday.

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