Dash for the ladder (3)
I believe the answer is:
run
I believe this is a double definition.
'dash' is the first definition.
(thesaurus)
'the ladder' is the second definition.
('run' can be a synonym of 'ladder')
'for' acts as a link.
(Other definitions for run that I've seen before include "Unbroken series" , "travel with > expedition" , "Race; manage" , "Operate; flow" , "Dash" .)