The phrase 'silver tongued' typically refers to someone who is smooth, articulate and persuasive in their communication skills. Antonyms for this phrase would include terms such as inarticulate, tongue-tied, clumsy, and awkward. These words describe individuals who may struggle to express themselves clearly, making it difficult for them to convince or inspire others. Other antonyms for 'silver tongued' might include blunt, frank, impolite, or tactless. These kinds of people may have difficulty in choosing their words carefully, and may not be skilled in the art of diplomacy or persuasion. Whilst a 'silver tongued' person is admired for their natural charm and charisma, their opposite traits can often have negative implications, such as lack of confidence or difficulty in social situations.