The following description of the 4 types of non-virtuous speech are from “The Way To Freedom” by the Dalai Lama:
“ The next four negative actions are deeds of speech.
The firs is telling lies. This includes speaking contrary to what one has seen, heard, or knows to be fact. Lying can be motivated by attachment, hatred, or ignorance. The intention is to confuse the other person, and it can be carried out either by speaking or nodding the head and gesturing with a hand. Any action done out of the intention to confuse someone constitutes the negative action of lying. If the other person hears it, that constitutes completion of this act.
Next is divisive talk. The intention is to cause dissension between friends or people in the spiritual community for one’s own sake or for he sake of others. Whether one succeeds in causing dissension or not, the moment the other person hears the divisive talk, that constitutes the completion of this act.
Next is verbal abuse. The intention is to speak harshly, and the deed is complete when the abusive words are heard by the person to whom they are directed. Abuse includes insulting others, speaking about their faults, whether true or untrue; if one does it to hurt the other person, it is abuse.
Next is senseless gossip. It is frivolousness without any purpose, and it can be motivated by any of the three poisons. One’s intention is simply to chat without any reason, to just gossip without any purpose.The execution of this act does not require a second person. You do not need a partner; you can do this by talking to yourself. Idle gossip would include talking about wars, the faults of others, or arguing just for the sake of argument. This would also include reading unimportant books out of attachment.”