Shut up adolescent losing vacuous argument (6)
I believe the answer is:
immure
'shut' is the definition.
(thesaurus)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for immure that I've seen before include "Sketches" , "Confine; wall in" , "Imprison, shut in" , "Confine in a closed space" , "Enclose within walls, incarcerate" .)