The most common and most likely answer to this crossword clue is the 4 plus 3 letter word IRON MAN
I
R
O
N
M
A
N
More clues leading to the result IRON MAN
- Fe-male superhero?
- Somehow I ran on, covering miles in demanding sportsevent
- Smooth fellow, a powerful athlete
- Tough sports event to flatten many, but not all
- Female? No!
- Spaced out female superhero
- Comic book character might be Female, cryptically
- Leg muscle’s first thing seen in country fellow of great strength
- Tough guy inviting female interpretation?
- Superhero name adopted by one Italian
Buddy explains!

The straight part
We know that "Superhero" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case superhero = iron man.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.