Full Idea
Metaphysical modal logic concerns metaphysical (or alethic) necessity and metaphysical (alethic) possibility, or necessity and possibility tout court - as opposed to such other types of modality as physical necessity, epistemic necessity etc.
Clarification
'tout court' means 'simply'
Gist of Idea
Metaphysical (alethic) modal logic concerns simple necessity and possibility (not physical, epistemic..)
Source
Nathan Salmon (The Logic of What Might Have Been [1989], Intro n2)
Book Reference
Salmon,Nathan: 'Metaphysics, Mathematics and Meaning' [OUP 2005], p.130