Traditional girl, one attending college in California (9)
I believe the answer is:
classical
'traditional' is the definition.
(I've seen this before)
'girl one attending college in california' is the wordplay.
'girl' becomes 'lassi' (I can't justify this - if you can you should believe this answer much more).
'one attending' is a charade indicator (letters next to each other).
'college' becomes 'c'.
'in' means one lot of letters goes inside another.
'california' becomes 'cal' (short for California).
'lassi'+'c'='lassic'
'lassic' inserted inside 'cal' is 'CLASSICAL'.
Can you help me to learn more?
(Other definitions for classical that I've seen before include "Type of music as opposed to pop, jazz etc" , "from an earlier time" , "Established - traditional - formal" , "Traditionally accepted" , "Accepted as standard" .)