The term "plain spoken" refers to someone who communicates in a straightforward and simple manner. Its antonyms include complicated, complex, and convoluted, which describe language that is difficult to understand. Another antonym is vague, which means unclear or ambiguous, as opposed to being direct and to the point. Evasive is also an antonym, which implies avoiding a direct answer or being deliberately obscure. Other antonyms for "plain spoken" include cryptic, enigmatic, and mysterious, which all suggest an intentional obscurity or concealment of meaning. Overall, antonyms of "plain spoken" emphasize the importance of clear and concise communication in effective discourse.