modal

US /ˈmoʊ.dəl/
UK /ˈmoʊ.dəl/
"modal" picture
1.

relating to or denoting a mode or form, as opposed to a substance or thing

:
The architect focused on the modal aspects of the building's design.
Philosophers often discuss the modal properties of existence.
2.

relating to or expressed in the mood of a verb

:
In grammar, 'can' and 'must' are examples of modal verbs.
The sentence structure requires a modal auxiliary verb.
1.

a modal verb

:
In English, 'will' is a common modal.
She used a modal to express possibility.