Defined

lynch mob  

     ( lynch mobs    plural  )

1       n-count   A lynch mob is an angry crowd of people who want to kill someone without a trial, because they believe that person has committed a crime.  

2       n-count   You can refer to a group of people as a lynch mob if they are very angry with someone because they believe that person has done something bad or wrong.  
Something approaching a lynch mob has been gathering against the Chancellor for even daring to consider higher interest rates.