False (adjective)

1. Not genuine; imitation or counterfeit.
2. Based on mistaken ideas, wrong beliefs, etc.
3. Not real, actual or truthful; not accurate or exact.
4. Intentionally misleading; deceitful.
5. Inconsistent with fact or reality; not true.

Origin:

Middle english fals, from old french, from latin falsus, past participle of fallere to deceive.

Examples:

1. The police discovered that the painting was a false Rembrandt.
2. She found out that his promises were false.
3. The company was accused of using false advertising.
4. The news were false and spread to deceive people.
5. He gave false testimony under oath.