Australia cheers maiden over - it's a cracker! (5)
I believe the answer is:
matzo
'a cracker' is the definition.
The answer and definition can be both things that one consumes for nourishment as well as being singular nouns.
Perhaps you can see a link between them that I can't see?
'australia cheers maiden over' is the wordplay.
'australia' becomes 'oz' (informal name for Australia).
'cheers' becomes 'ta' (both can informally mean thank you).
'maiden' becomes 'm' (cricket abbreviation).
'over' is a reversal indicator.
'oz'+'ta'+'m'='oztam'
'oztam' reversed gives 'MATZO'.
'it's' acts as a link.
Can you help me to learn more?
(Other definitions for matzo that I've seen before include "Unleavened biscuit" , "Crisp flat unleavened bread" , "Unleavened wafer" , "Unleavened bread eaten at Passover" , "Brittle flat bread eaten at Passover" .)