Certain varieties of grass will reportedly cause bewilderment (9)
I believe the answer is:
bamboozle
'certain varieties of grass will reportedly cause bewilderment' is the definition.
I can't judge whether this defines the answer.
'grass will reportedly cause bewilderment' is the wordplay.
I cannot quite see how this works, but
'grass' could be 'bamboo' (I've seen this before) and 'bamboo' is located in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for bamboozle that I've seen before include "Fool" , "Confuse" , "Puzzle" , "Hoodwink" , "Lead by the nose" .)
