Liberals seek control. Total control. Of everybody. Not only of your actions, your thoughts as well.
We saw that in the Soviet Union and other Left-Wing Totalitarian states. They do that by changing the language and using your own social mores against you. If you let them set the structure of the conversation by defining the terms, you are already defeated, because inside their structure, there is no way to defend a position contrary to theirs.
Words have what is called, for a lack of a better term, an "Emotional Index." This means that a word or term will cause an emotional response in the person hearing or reading the term. The word "Friend" produces a positive index because we think of our friends and our connection with them when we hear or see the word. Likewise, "Enemy" produces a similar number but in the negative direction.
So, when Liberals try to convince you to like something you don't like, they will change the terms, from words that have a strong negative index, to words with either a less negative index, or even a positive index. If they can, they will use words outside of the vocabulary of a average person, then define the word how they want it defined, rather than what it really means.
Case in point: "Illegal Aliens," used to denote citizens of other countries who are entering the United States without following the laws and procedures established for the orderly processing of people who wish to become Citizens of the United States. Liberals don't like that term, because, "People are not illegal." So, they want you to use the term "Undocumented Immigrant."
When we use the term "Alien," we are talking about definitions like,"a foreigner, especially one who is not a naturalized citizen of the country where they are living," or "relating, belonging, or owing allegiance to another country or government." To prefix the term "Alien" with "Illegal" you are stating that a citizen of one country has moved to another country and is now living in the second country without going through the process as defined by law to renounce their citizenship of their former country.
Now let's take a look at the second term, "Undocumented Immigrant." Both of these words have way lower negative index scores than the first term. After all, the United States is a nation built on immigrants, wasn't it? So, we switch from "Alien," which also means unfamiliar, while also invoking at least some fear, because people instinctively fear that which is unknown, or alien to them. Thus we change from a big negative index, to a neutral or even a positive index. Then the prefix adjective, "Undocumented," which means "not supported by documentary evidence."
We can rationalize this by saying, "If I'm driving my car and don't have my drivers license when I get stopped, I'm undocumented." Or you can think about that "undocumented expense report" because you didn't provide the necessary paperwork to justify your claim. You can almost begin to think that the Undocumented Immigrant belongs here, they just haven't made it through the bureaucratic red tape to become full citizens yet. Again, when comparing the indexes between "Illegal" and "Undocumented," the index is way lower for the latter.
So, by getting you to accept their term of "Undocumented Immigrant," you have already lost the argument because you have stopped using a term with a great negative index, to one with a slight positive index. You are now taking a position against someone that you yourself would feel favorable towards, because of the change in the term.
If you have ever read Nineteen Eighty-Four by George Orwell, you read about Big Brother changing the language. If you can change the language to eliminate words like "Freedom, " "Individual" and the like, how can someone conceive of these ideas to challenge who is in control? Don't play their game. Use your terms and definitions, and communicate them clearly and often so people know what you are talking about.
When you are clear and consistent in your message, while your opponent is trying to obfuscate what they are saying and changing their message as facts against them become evident, most peoples BS meter will start to go off. Just remember, you can only win people over to your side who are open to new ideas and concepts. If someone has their reputation entrenched and they are heavily emotionally invested in a position, you won't win them over. Your object is to win those who are watching the conversation to your point of view.