In spite of how most modern stadiums are built? (15)
I believe the answer is:
notwithstanding
'in spite' is the definition.
(thesaurus)
'of how most modern stadiums are built?' is the wordplay.
I cannot really see how this works, but
'of' could be 'o' and 'o' is found within the answer.
'modern' could be 'in' (I've seen this in other clues) and 'in' is located in the answer.
'are' could be 'a' (short for 'are', historical unit of measurement) and 'a' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for notwithstanding that I've seen before include "anyway" , "... in spite" , "Although" , "Even so" , "yet" .)