The most common and most likely answer to this crossword clue is the 6 letter word DEFEND
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D
More clues leading to the result DEFEND
- FBI agent backed objective to protect
- Keep from harm in brilliant finish
- Guard having mainly brave aim
- US agent returned to kill guard
- Guard fed up with outcome
- Champion fed up before finish
- Guard provided meal for revolutionary before death
- Guard fed up with dissolution
- Be obliged to admit fellow sent north is on the tail of Red Guard
- Guard appears fed up over tip
Buddy explains!

The straight part
We know that "protect" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case protect = defend.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 DEFEND mean?
DEFEND verb- To ward off attacks against; to fight to protect; to guard.
- To support by words or writing; to vindicate, talk in favour of.
- To make legal defence of; to represent (the accused).
- To focus one's energies and talents on preventing opponents from scoring, as opposed to focusing on scoring.
- To attempt to retain a title, or attempt to reach the same stage in a competition as one did in the previous edition of that competition.
- To call a raise from the big blind.
- To ward off, repel (an attack or attacker).
- To prevent, to keep (from doing something).
- To prohibit, forbid.