dual

Having two roles, purposes, identities, or other features at the same time.

• This room has a dual purpose.
• She has dual citizenship.
• His dual role as teacher and coach keeps him busy.

Similar words: twofold, double

Opposites: single

Common phrases: dual role, dual purpose, dual citizenship

Having two parts that work together or do similar jobs.

• The car has dual controls.
• Dual cameras allow the phone to capture more detail.
• This machine uses dual motors to lift heavy loads.

Similar words: double, twin

Opposites: single

Common phrases: dual controls, dual motors, dual cameras

Describing a word form used for exactly two people or things in some languages.

• This noun has a dual form.
• Arabic uses the dual number for pairs.
• The students compared singular, dual, and plural pronouns.

Common phrases: dual number, dual form, dual pronouns

A solid shape made by exchanging another solid’s faces and corners, with matching connections.

• Every cube has an octahedral dual.
• We constructed the dual by placing a vertex on each face.
• The two polyhedra are duals of each other.

How to use it: dual of something (The cube is the dual of the octahedron.)

Common phrases: dual of something, regular dual, polyhedral dual