A foolish sheep overturned flowering plant (9)
I believe the answer is:
amaryllis
'flowering plant' is the definition.
The answer and definition can be both plants as well as being singular nouns.
Perhaps there's an association between them I don't understand?
'a foolish sheep overturned' is the wordplay.
'foolish' becomes 'silly' (similar in meaning).
'sheep' becomes 'ram' (male sheep).
'overturned' is a reversal indicator.
'silly'+'ram'='sillyram'
'sillyram' in reverse letter order is 'maryllis'.
'a'+'maryllis'='AMARYLLIS'
Can you help me to learn more?
(Other definitions for amaryllis that I've seen before include "Plant with showy flowers - I rally Sam (anag)" , "Large-flowered bulb" , "Lily-like plant" , "Trumpet-flowered bulb" , "belladonna lily brought this about" .)