A little bit of straw is proving essential (4)
I believe the answer is:
wisp
'a little bit' is the definition.
Although both the answer and definition are singular nouns, I don't understand how they can define each other.
'of straw is proving essential' is the wordplay.
'of' indicates the answer is hidden within the clue.
'WISP' can be found hidden inside 'straw is proving essential'.
Can you help me to learn more?
(Other definitions for wisp that I've seen before include "Small tuft of hair" , "Shred" , "whose will is so elusive?" , "Thin fine strand" , "Gauzy strand" .)