A girl in distress — something sought by knights (5)
I believe the answer is:
grail
'something sought by knights' is the definition.
I can't judge whether this defines the answer.
'a girl in distress' is the wordplay.
'in distress' indicates anagramming the letters.
'a'+'girl'='agirl'
'agirl' anagrammed gives 'GRAIL'.
Can you help me to learn more?
(Other definitions for grail that I've seen before include "The Holy ..., the legendary chalice used at the Last Supper" , "Legendary cup sought by knights" , "Famous chalice" , "Legendary holy item" , "Object of King Arthur's quest" .)