send someone to Coventry
send (one) to Coventry
To ostracize; to ignore or refuse to communicate with one, typically as a form of punishment. Primarily heard in UK. When I refused to help them cheat, the other students sent me to Coventry.
send someone to Coventryrefuse to associate with or speak to someone. chiefly British
This expression, which dates from the mid 18th century, is thought by some to stem from the extreme unpopularity of soldiers stationed in Coventry, who were cut off socially by the citizens. Another suggestion is that the phrase arose because Royalist prisoners were sent to Coventry during the English Civil War, the city being staunchly Parliamentarian.