One of a class of men who taught eloquence, philosophy, and politics in ancient Greece; especially, one of those who, by their fallacious but plausible reasoning, puzzled inquirers after truth, weakened the faith of the people, and drew upon themselves general hatred and contempt.

Hence, an impostor in argument; a captious or fallacious reasoner.

any of a group of Greek philosophers and teachers in the 5th century BC who speculated on a wide range of subjects

someone whose reasoning is subtle and often specious

a person who is skilled at influencing audiences and winning arguments

From the ancient Greek word "sophia" meaning "wisdom" in the sense of possessing a certain art or skill (techne). This term was used as the name for teachers of rhetoric, and in that context took on the meaning of "clever" as in "clever speaker".

The Sophist (Greek: Σοφιστής) is one of the late Dialogues of Plato, which was written much more lately than the Parmenides and the Theaetetus, probably in 360 BC. After he criticized his own Theory of Forms in the Parmenides, Plato proceeds in the Sophist with a new conception of the Forms, more mundane and down-to-earth, and makes clearer the epistemological and metaphysical puzzles of the Parmenides; therefore he is referring to that dialogue between Parmenides and young Socrates, which was written probably much earlier than the Sophist. Furthermore, he shows his expertise in Dialectic, as he applies it in this Dialogue in order to define the Sophist.