Words map your inner concepts to reality and they allow that meaning to be conveyed to others. When you and your peers agree on the meaning of a word in a consistent way with reality then the word becomes a powerful tool for learning and adapting quickly to the world.

This power can be manipulated though. When a person takes a word that already has an agreed upon meaning and adds on some other thoughts of their own they can alter the thought processes of the other person.

This can be a good thing if that alteration reflects a more accurate representation of the word, but if instead reflects only a selfish interest of the other person then it becomes propaganda, a way of thought control.

Expand your vocabulary, never be afraid of adding new words. Just make sure that you don't fall into the trap of living only in your thoughts, you are living in the real world and your words should reflect its immense scope, truth and beauty.