The most common and most likely answer to this crossword clue is the 7 letter word AVENGER
I've seen this crossword clue in The Times
A
V
E
N
G
E
R
More clues leading to the result AVENGER
- One settles score as compared with English in rage
- One getting back around half five seeing red
- State invaded by English party retaliating
- Person seeking retribution in Newhaven, Germanic
- Lying in state, English seeker of justice
- Swear to overwhelm English member of superhero squad
- Agent of retribution, English, lying in state
- Seen in temper, case of volatile nemesis
- One retaliating, losing rag even?
- One settles score against English in rage
Buddy explains!

The straight part
We know that "Person seeking retribution" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case person seeking retribution = avenger.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.
What does AVENGER mean?
AVENGER noun- One who avenges or vindicates
- One who takes vengeance.