The problem is simply that I do not completely understand the principle of lashon hara.
One definition I often see is that lashon hara is spreading true (or also false in broader terms), derogatory information about someone else and that it harms three people: the speaker, the listener and the subject of the gossip. (definition 1)
However, I also read that lashon hara is all evil, derogatory speech about or against somebody [and if publicized, it would cause the subject physical or monetary damage, or would cause him anguish or fear] (I have put the last part in brackets because I read a text which defines lashon hara without this part). (defintion 2)
In the first definition, it seems to me, that the subject is not present when somebody speaks lashon hara about him, or if the subject is in fact present, there is also at least one other person present who hears the negative speech.
In the second definition, however, it appears to me that lashon hara does not necessarily needs to involve a third person and can also occur between only two actors - one is the person who speaks lashon hara and the other is the one who is the subject of this evil speech.
Is the second definition also correct? Can I speak lashon hara to somebody if there is no one else who could possibly hear what I've said? In other words, can there be lashon hara between only two people or does there has to be at least a third person involved?
I would be glad if you could provide me with a source