Refers to a cutting or incisive way of speaking, often in debate or argument. Can imply both sharp criticism and persuasive eloquence.
His sharp tongue was so incisive that no one could argue back.
At the debate, she cornered her opponent with her eloquence.
sharp-tongued; cutting; scathing
Compound of 舌 (tongue) and 鋒 (point of a sword), literally 'sword-tongue'. The exact historical derivation is uncertain, but the spelling is conventionally associated with sharp speech.