Nod (2-5)
'nod' is the definition.
(thesaurus)
This is all the clue.
(Other definitions for go-ahead that I've seen before include "Pioneering (green light?)" , "Enterprisingly progressive" , "Permission to proceed" , "Up-and-coming - authorisation" , "Enterprising" .)
'nod' is the definition.
(thesaurus)
This is all the clue.
(Other definitions for bow that I've seen before include "Bend from the waist in deference" , "at front of vessel" , "Front of boat" , "Arc" , "Bending in reverence or shame" .)