In the company of man, go astray (5)
I believe the answer is:
among
'in the company of' is the definition.
('among' means 'in the company of' or 'with')
'man go astray' is the wordplay.
'astray' is an anagram indicator.
'man'+'go'='mango'
'mango' with letters rearranged gives 'AMONG'.
(Other definitions for among that I've seen before include "when in company" , "Surrounded by" , "Included with - inside" , "in a group" , "In the midst of (others)" .)