mo|dal|i|ty «moh DAL uh tee», noun, plural -ties.
1. the quality or fact of being modal.
2. a modal attribute or circumstance; mode.
3. Medicine. a form, method, or apparatus of therapy, especially physiotherapy or electrotherapy.
4. Logic. the character of a proposition as asserting or denying necessarily, possibly, or without such qualification.
Useful english dictionary. 2012.