He parades around foremost of army units (9)
I believe the answer is:
spearhead
'he parades around foremost of army units' is the definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
'he parades around' is the wordplay.
'around' is an anagram indicator.
'he'+'parades'='heparades'
'heparades' is an anagram of 'SPEARHEAD'.
Can you help me to learn more?
(Other definitions for spearhead that I've seen before include "tip on manual weapon" , "Take the lead in" , "Take charge of" , "initiate attack" , "the sort of point best missed" .)