The adjective erroneous means a belief, opinion or process that is wrong or false or only partly true.

Synonyms are invalid, inaccurate, mistaken, or spurious.

The word origins from Old French (late 14th century) erroneus and directly from Latin erroneus meaning “vagrant, wandering”. It comes from erronem meaning “a wanderer, vagabond”, from past participle stem of errare meaning “to wander, to err”.

After careful studies and experiments, they come up with an erroneous conclusion.

He was accused of erroneous teaching and was banned from the organization.

We tend to make erroneous judgments.