King James Bible Dictionary

A Jewish political party who sympathized with (Mark 3:6; 12:13; Matt, 22:16; Luke 20:20) the Herodian rulers in their general policy of government, and in the social customs which they introduced from Rome. They were at one with the Sadducees in holding the duty of submission to Rome, and of supporting the Herods on the throne. (Comp. Mark 8:15; Matthew 16:6.)

A Jewish faction.

Seek to entangle Jesus
Matthew 22:16; Mark 12:13

Conspire to slay Jesus
Mark 3:6; Mark 12:13

(from Herod). (Matthew 22:15) ff.; Mark 12:13 ff. Canon Cook describes these persons as "that party among the Jews who were supporters of the Herodian family as the last hope of retaining for the Jews a fragment of national government, as distinguished from absolute dependence upon Rome as a province of the empire. Supporters of the family of Herod, who held their dominions by the grant of the Roman emperor, would be in favor of paying tribute to the supreme power. (Matthew 22:16)

HERO'DIANS, noun A sect among the Jews, which took this name from Herod; but authors are not agreed as to their peculiar notions.