Acting superior to others and looking down on people you consider inferior or less important.
From 'snob,' possibly from 'sine nobilitate' (without nobility) abbreviated in Cambridge to describe non-noble students. The term evolved to mean someone who acts more refined than they actually are.
The origin of 'snob' might come from Latin abbreviations at fancy universities—ironic that the word for 'acting superior' came from marking who WASN'T officially superior! Language loves these reversals.
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