dual
//ˈduː.əl//
Adjective
dualCanonical form
1
Having two parts, elements, or aspects.
This device has a dual function: it can be used as both a phone and a camera.
2
Serving a double purpose or function.
This room has a dual purpose: it serves as both an office and a guest bedroom.
Noun
1
A grammatical number category referring to exactly two entities, found in some languages.
Ancient Greek has a dual number to indicate exactly two people or things.
2
Something that has two parts or aspects.
This device is a dual of hardware and software.