Maths expert's lager tab is recalculated (10)
I believe the answer is:
'maths' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how they can define each other.
'expert's lager tab is recalculated' is the wordplay.
'lager tab is' anagrams to 'ALGEBRAIST'.
However, I am not sure how this is indicated.
Can you help me to learn more?