cold shoulder
cold shoulder  {n.},  {informal}
Unfriendly treatment of a person, a showing of dislike for a person or of looking down on a person. — Used in the cliches "give the cold shoulder" or "turn a cold shoulder to" or "get the cold shoulder". 
When Bob asked Mary for a date she gave him the cold shoulder.
The membership committee turned a cold shoulder to Jim's request to join the club.
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Source: A Dictionary of American Idioms

