Eccentric pal meets raging mob with coolness (6)
I believe the answer is:
aplomb
'coolness' is the definition.
(I know that coolness can be written as aplomb)
'eccentric pal meets raging mob' is the wordplay.
'eccentric' indicates an anagram.
'meets' is a charade indicator (letters next to each other).
'raging' is an anagram indicator.
'pal' is an anagram of 'apl'.
'mob' is an anagram of 'omb'.
'apl'+'omb'='APLOMB'
'with' is the link.
(Other definitions for aplomb that I've seen before include "Nonchalant confidence" , "Self-satisfied poise" , "Self-satisfied dignity and confidence" , "Self-satisfied assurance" , "'Poise, sang-froid (6)'" .)