Brave man; he has heart of iron (4)
I believe the answer is:
hero
'brave man' is the definition.
(a hero is a brave person)
'he has heart of iron' is the wordplay.
'has' says to put letters next to each other.
'heart of' indicates the central letters.
The central letters of 'iron' are 'ro'.
'he'+'ro'='HERO'
(Other definitions for hero that I've seen before include "Conqueror" , "Leander's lover - a person of courage" , "Chief good guy in a story" , "Very brave man" , "Exceptionally brave person" .)