Caged bird one lost in move (5)
I believe the answer is:
budge
'move' is the definition.
(to budge is to move slightly)
I don't understand the rest of the clue.
(Other definitions for budge that I've seen before include "Shift slightly, or cause to alter position" , "Move, stir" , "Make a slight movement" , "Make the slightest movement" , "Shift or yield" .)