Definition
instead of being on topic about the argument, the write changes the argument with something unrelated
instead of being on topic about the argument, the write changes the argument with something unrelated
Examples
To avoid answering what the certification was for, the man changed the subject and brought up the argument about certification being a waste of time. He was asked a question he didn't want to answer and so he was "ignoring the question".
When Mitt Romney was asked the question if he would arrest the patient and his doctor if they used medical marijuana, he ignored it and said that he did not support medical marijuana instead of directly answering the question. He changed the argument to another topic.