That's called "PROJECTION"
i think it a sin only if the person that you call a liar is not a liar
liar
u can call them a user or liar i guess
a liar. they say liar so many times it begins to sound like lyra and liar are the same! :)
Normally a liar.
braggart
a liar
psycho
habitual liar
A very good liar!
A person who lies only when necessary can be described as a "compulsive liar" or "occasional liar."
You can call someone who does not lie honest, truthful, trustworthy, or sincere.