Full Idea
For the regularity version of dispositional essentialism about laws, laws are those regularities whose truth is guaranteed by the essential dispositional nature of one or more of the constituents. Regularities that supervene on such laws are also laws.
Gist of Idea
Dispositional essentialism says laws (and laws about laws) are guaranteed regularities
Source
Alexander Bird (Nature's Metaphysics [2007], 3.1.2)
Book Reference
Bird,Alexander: 'Nature's Metaphysics' [OUP 2007], p.46
A Reaction
Even if you accept necessary behaviour resulting from essential dispositions, you still need to distinguish the important regularities from the accidental ones, so the word 'guarantee' is helpful, even if it raises lots of difficulties.