Get up to terrible increase in salary (5)
I believe the answer is:
arise
'get up' is the definition.
(synonyms)
'terrible increase in salary' is the wordplay.
I cannot really understand how this works, but
'increase' could be 'rise' (rise is a kind of increase) and 'rise' is located in the answer.
A single letter 'a' remains which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'to' acts as a link.
Can you help me to learn more?
(Other definitions for arise that I've seen before include "Get up or come up" , "Spring - get up" , "Turn up" , "Emerge" , "Happen" .)