Bias
Words are the meanings of thoughts. Thoughts are our minds analysis of information. To communicate information to others we must use our words. All information is composed of information that is preexisting. To break down all information to its most rudimentary logical components you would be left with only that which is self evident. In order to compose new information you must analyze that which is preexisting.
Bias corrupts the purity of a mind's analysis of existence. Hence, it alters the clarity of one's thoughts and thus changes the meanings of the biased individuals words. One could conject that the majority of human miscommunication errors are a direct result of bias.