No big case for investing funds in underwear (5,8)
I believe the answer is:
small capitals
'no big case for investing funds in underwear' is the definition.
I can't judge whether this definition defines the answer.
'investing funds in underwear' is the wordplay.
'investing' indicates putting letters inside (inserted letters are taken in or invested).
'funds in' becomes 'capital' (I've seen this before. I am not sure about the 'in' bit.).
'underwear' becomes 'smalls' (I've seen this before).
'capital' going within 'smalls' is 'SMALL CAPITALS'.
Can you help me to learn more?
(Other definitions for small capitals that I've seen before include "places like Vaduz?" , "places like thirty two [AJACCIO] ?" , "Short letters" , "Upper-case letters of same size as lower-case" , "Type" .)