A chief is in front (5)
I believe the answer is:
ahead
'in front' is the definition.
('ahead' can be a synonym of 'in front')
'a chief' is the wordplay.
'chief' becomes 'head' ('head' can be a synonym of 'chief'**).
'a'+'head'='AHEAD'
'is' is the link.
(Other definitions for ahead that I've seen before include "In the vanguard" , "advanced" , "In the lead, in advance" , "at pole" , "What's down the road" .)