George Orwell called it "Newspeak" ... and it won't contain words for ideas of which the elites disapprove.
Gene Wolfe expanded on the idea in his “Book of the New Sun” series with a country (called Ascia) where not only was there an imposed language by the government, but in fact the only sentences or phrases one could utter had to be quotes from “Approved Thought”... government approved propaganda texts.
There is one scene were a person who grows up in this society tries to tell a story, using only these “approved thought” phrases. It’s quite funny. In order to say “the man was beaten mercilessly”, he has to say “No one is to receive more than 100 blows.” as that is the closest “approved thought” to what he actually wants to describe.
Here’s a link to the chapter in question and some context about it:
https://www.gwern.net/docs/culture/1983-wolfe-thecitadeloftheautarch-thejustman