Jehovah's Witnesses are not only oblivious to the fact that their org has changed the historical date of Jerusalem's destruction to 607 BCE, but also that their hierarchy can alter meanings in the English language! According to virtually every definition, the word CHRISTENDOM effectively means being a part of Christianity.
https://www.merriam-webster.com/dictionary/Christendom -
1: Christianity
2: The part of the world in which Christianity prevails
https://en.wikipedia.org/wiki/Christendom
...the "Christian world": worldwide community of Christians, the adherents of Christianity, the Christian-majority countries, the countries in which Christianity dominates or prevails...
https://en.oxforddictionaries.com/definition/christendom - The
worldwide body or society of Christians.
Jehovah's Witnesses' indoctrination teaches them that the word CHRISTENDOM is a derogatory term which describes false Christianity and false Christians.
Wake up JW's - you are all members of Christendom!