What is Sophists?

Sophists definition and meaning on Dictionary terms:
(often initial capital letter) Greek History. any of a class of professional teachers in ancient Greece who gave instruction in various fields, as in general culture, rhetoric, politics, or disputation.a person belonging to this class at a later period who, while professing to teach skill in reasoning, concerned himself with ingenuity and specious effectiveness rather than soundness of argument.

a person who reasons adroitly and speciously rather than soundly.
a philosopher.