Full Idea
We use the terms 'power' and 'disposition' as equivalent, but some reserve the term 'disposition' for powers that tend to be manifested.
Gist of Idea
We say 'power' and 'disposition' are equivalent, but some say dispositions are manifestable
Source
S.Mumford/R.Lill Anjum (Getting Causes from Powers [2011], 1.1)
Book Reference
Anjum,R.J./Mumford,S.: 'Getting Causes from Powers' [OUP 2011], p.4
A Reaction
[For the latter they cite Fara 2005] There is some point to the latter distinction, as separating those powers that relate to the actual world from those powers that could never be triggered in actuality. I would say a power produces a disposition.