A large wagon used to carry a band of musicians in a parade. / (figuratively) A current movement that attracts wide support.

plural of bandwagon

(politics) The practice of joining the prevailing side.

plural of bandwagoner

Someone who supports or participates in something only because it is popular or successful.

The tendency to jump on the bandwagon, i.e. to join a craze or trend, sometimes for profit.

(idiomatic) To profit from a craze; to join a trend.

(logic) argumentum ad populum.

(sociology) the observation that people often do or believe what they think many other people do.

plural of bandwagon fallacy