Before jaunt, I loaded cases (5)
I believe the answer is:
until
'before' is the definition.
(thesaurus)
'jaunt i loaded cases' is the wordplay.
'cases' indicates a hidden word.
'UNTIL' is hidden within 'jaunt i loaded'.
(Other definitions for until that I've seen before include "Before a given time" , "Up to (a point in time)" , "Unlit (anag.)" , "Up to that moment" , "As late as" .)