du·al (dəl, dy-)
1. Composed of two usually like or complementary parts; double: dual controls for pilot and copilot; a car with dual exhaust pipes.
2. Having a double character or purpose: a belief in the dual nature of reality.
3. Grammar Of, relating to, or being a number category that indicates two persons or things, as in Greek, Sanskrit, and Old English.
1. The dual number.
2. An inflected form of a noun, adjective, pronoun, or verb used with two items or people.
[Latin duālis, from duo, two; see dwo- in the Appendix of Indo-European roots.]
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