phony

Short definition from Wiktionary

Adjective

1. 1
   Fraudulent; fake; having a misleading appearance.

Noun

1. 1
   A person who assumes an identity or quality other than their own.
2. 2
   A person who professes beliefs or opinions that they do not hold.
3. 3
   Anything fraudulent or fake.

Verb

1. 1
   To fake.