The most common and most likely answer to this crossword clue is the 8 letter word JEANETTE
I've seen this crossword clue in The Times
J
E
A
N
E
T
T
E
More clues leading to the result JEANETTE
Buddy explains!

The straight part
We know that "What may protect legs" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case what may protect legs = jeanette.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.