Etymology Qn. for July 14th - Dev

In 1880, Charles Stewart Parnell gave a speech in Ireland to a crowd of Land League members. During his speech, he asked the crowd: "What do you do with a tenant who bids for a farm from which his neighbor has been evicted?". The response from the crowd was: "kill him", "shoot him". Parnell replied:

I wish to point out to you a very much better way – a more Christian and charitable way, which will give the lost man an opportunity of repenting. When a man takes a farm from which another has been evicted, you must shun him on the roadside when you meet him–you must shun him in the streets of the town–you must shun him in the shop – you must shun him on the fair green and in the market place, and even in the place of worship, by leaving him alone, by putting him in moral Coventry, by isolating him from the rest of the country, as if he were the leper of old – you must show him your detestation of the crime he committed.

This speech set out the Land League's powerful weapon which was first applied to the land agent Charles X. As usual, identify X.