Revolutionary caste's middle class members making errors (4-3)
I believe the answer is:
slip-ups
'errors' is the definition.
(I know this)
'revolutionary caste's middle class members' is the wordplay.
'revolutionary' is a reversal indicator (letters revolve around).
'caste's' becomes 'Vaisya's' (Vaisya is an example).
'middle' says to take the centre.
'class members' becomes 'pupils' (I've seen this in another clue).
The central letter of 'vaisyas' is 's'.
's'+'pupils'='spupils'
'spupils' written backwards gives 'SLIP-UPS'.
'making' is the link.
(Another definition for slip-ups that I've seen is " Errors".)