To be sent to Coventry
Meaning: to be banned, greeted with a chilly silence.
Origin
The popular story is that the people of Coventry were at one time so hostile to soldiers that any woman seen talking to one was ostracized. Thus, any soldier unfortunate enough to be sent to Coventry was cut off from all friendly or social intercourse.
But there is another, and perhaps more likely, version that Coventry was a Parliamentary stronghold on the Civil War, and troublesome Royalist prisoners were sent there for safe keeping. Coventry, the name, is a corruption of Covent-town. The suffix -try is Celtic for 'dwelling'. Before the Reformation Coventry was far-famed for the number of its convents, or religious establishments.
Notes
*Civil War - the war between Charles I of England and the Parliament, from 1642 yo 1646 and from 1648 to 1652,
**The Reformation - the great religious, social and political movement in Europe in the XVI century which established Protestantism, the chief principle of which is strict conformity ti the Bible.
Example
...afret having made a few constrained and unnatural demonstrations of friendliness, they left him alone. It was almost, Anthony found, like being sent to Coventry. (A. Huxley, 'Eyeless in Gaza', ch. VI)