The most common and most likely answer to this crossword clue is the 6 letter word SAFETY
I've seen this crossword clue in The Times
S
A
F
E
T
Y
More clues leading to the result SAFETY
- Iron anklet finally brought in for one’s security
- Note with iron put in farm structure for protection
- Sort of pin you find in numbers?
- Security, for example, involving iron anklet ultimately
- Shelter, for example, to accommodate most of the characters in gala
- Protection, for example, hiding iron shirt
- Report covering achievement, having abandoned a refuge
- Fellow on film interrupting, for example, snooker shot
- Security perhaps covering most of fair
- Half-hearted measures adopted by state security
Buddy explains!

The straight part
We know that "protection" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case protection = safety.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 SAFETY mean?
SAFETY noun- The condition or feeling of being safe; security; certainty.
- A mechanism on a weapon or dangerous equipment designed to prevent accidental firing.
- An instance of a player being sacked or tackled in the end zone, or stepping out of the end zone and off the field, resulting in two points to the opposite team.
- Any of the defensive players who are in position furthest from the line of scrimmage and whose responsibility is to defend against passes as well as to be the tacklers of last resort.
- A safety squeeze.
- Preservation from escape; close custody.
- A safety bicycle.
- To secure (a mechanical component, as in aviation) to keep it from becoming detached even under vibration.
- To secure a firing pin, as in guns, to keep the gun from firing