In a range of literary works, “couth” is deployed as an archaic modal verb conveying ability, knowledge, or proficiency. Writers employ it to indicate that a character “knew well” how to act or perform a task, as seen when Aristotle “well couth” his teachings ([1]) or when a craftsman “couth” twist intricate silk threads ([2], [3]). At times, the term functions specifically as the past tense of “can,” emphasizing a demonstrated capacity, a nuance directly noted by one commentator ([4]). Moreover, “couth” appears in contexts of martial leadership and practical skill—from eliciting loyalty by managing daily affairs to commanding respect on the battlefield ([5], [6])—thereby enriching narrative moments with a historically textured expression of capability.