Sad university pupil's introduction to crossword-making (9)
I believe the answer is:
upsetting
'sad' is the definition.
Both the definition and answer are adjectives. Maybe you can see a link between them that I can't see?
'university pupil's introduction to crossword-making' is the wordplay.
'introduction' indicates taking the first letters.
'to crossword making' becomes 'setting' (I can't justify this - if you can you should give a lot more credence to this answer).
The initial letters of 'university pupils' is 'up'.
'up'+'setting'='UPSETTING'
Can you help me to learn more?
(Other definitions for upsetting that I've seen before include "sad?" , "Likely to put out" , "Tipping" , "worrying" , "Alarming" .)