Only first three characters in college getting pass (3)
I believe the answer is:
col
'pass' is the definition.
(col is a term for a mountain pass)
'only first three characters in college getting' is the wordplay.
'only first three' becomes 'co' (I can't explain this - if you can you should give a lot more credence to this answer).
'characters in' indicates the central letters.
'getting' means one lot of letters go next to another.
The central letter of 'college' is 'l'.
'co'+'l'='COL'
(Other definitions for col that I've seen before include "Mustard" , "Lowest point of ridge between two peaks" , "A pass through ridge" , "Officer" , "Somewhere up on the mountain" .)