Lead engineer shaped era (9)
I believe the answer is:
spearhead
'lead' is the definition.
(I know that spearhead is a type of lead)
'engineer shaped era' is the wordplay.
'engineer' indicates an anagram.
'shaped'+'era'='shapedera'
'shapedera' is an anagram of 'SPEARHEAD'.
(Other definitions for spearhead that I've seen before include "Leading force in a military attack" , "Group leading an attack" , "tip on manual weapon" , "those at the forefront" , "Advanced troops" .)