Irritable about university intake, principally, after good financial gift (8)

I believe the answer is:

gratuity

I'm a little stuck... Click here to teach me more about this clue!

'financial gift' is the definition.
'gratuity' can be an answer for 'gift' (gratuity is a kind of gift). I'm not sure about the 'financial' bit.

'irritable about university intake principally after good' is the wordplay.
'irritable' becomes 'ratty' (I've seen this before).
'about' indicates putting letters inside.
'principally' suggests taking the first letters.
'after' means one lot of letters go next to another.
'good' becomes 'g' (abbreviation).
The first letters of 'university intake' is 'ui'.
'ratty' going around 'ui' is 'ratuity'.
'ratuity' after 'g' is 'GRATUITY'.

Can you help me to learn more?

(Other definitions for gratuity that I've seen before include "present" , "Tip (to waiter)" .)

I've seen this clue in The Telegraph.

Want a hint initially instead of a full solution? Install my app