The word "was frank" is an expression that implies honesty and openness in communication. Its antonyms would be phrases or words that suggest the opposite qualities, such as insincerity, dishonesty, secrecy, or deceit. Examples of antonyms for "was frank" includes "was disingenuous," "was guarded," "was evasive," "was insincere," "was deceitful," "was untruthful," "was mendacious," or "was duplicitous." Using antonyms for "was frank" can help to suggest a different type of communication and tone to a conversation, depending on the context and the speaker's intent.