With energy, canter and get hitched on the run (5)
I believe the answer is:
elope
'get hitched on the run' is the definition.
(I've seen this in another clue)
'with energy canter' is the wordplay.
'with' says to put letters next to each other.
'energy' becomes 'e' (physics symbol as in E=mc2).
'canter' becomes 'lope' (synonyms).
'e' put next to 'lope' is 'ELOPE'.
'and' acts as a link.
(Other definitions for elope that I've seen before include "Bolt" , "Run away to Gretna Green?" , "(Lovers) run away" , "go off to the match?" , "Run away to wed" .)