Commentator's staunch European (5)
I believe the answer is:
czech
'european' is the definition.
(Czech is an example)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for czech that I've seen before include "from central Europe" , "Bohemian" , "One from Brno" , "Native of Prague, perhaps" , "Eg, a native of Prague" .)