(n.) A person who knowingly utters falsehood; one who lies.

Ananias Baron Munchausen Father of Lies Satan Sir John Mandeville consummate liar dirty liar equivocator fabricator fabulist false witness falsifier fibber fibster habitual liar mythomaniac palterer pathological liar perjurer prevaricator pseudologist pseudologue spinner of yarns storyteller teller of tales yarn spinner yarner