Worker catches bus in order to save (7)
I believe the answer is:
husband
'save' is the definition.
(husbanding is a kind of saving)
'worker catches bus in order' is the wordplay.
'worker' becomes 'hand' (hand is a kind of worker).
'catches' is an insertion indicator.
'in order' indicates anagramming the letters (the letters in a new order).
'bus' anagrammed gives 'usb'.
'hand' going around 'usb' is 'HUSBAND'.
'to' is the link.
(Other definitions for husband that I've seen before include "be economical" , "manage wisely" , "Man United" , "Better half's other half?" , "Use resources economically" .)