Cops all high on E pass out? (8)
I believe the answer is:
collapse
'pass out?' is the definition.
(thesaurus)
'cops all high on e' is the wordplay.
'high' is an anagram indicator (like drunk).
'on' means one lot of letters go next to another.
'cops'+'all'='copsall'
'copsall' anagrammed gives 'collaps'.
'collaps'+'e'='COLLAPSE'
(Other definitions for collapse that I've seen before include "Break down - fall" , "Slump" , "Founder" , "Faint and fall" , "Fall down or lose strength suddenly" .)