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alcēdōnĭa (halc-), ōrum, n. [alcedo], the fourteen winter days during which the kingfisher broods and the sea is calm, v. alcedo.
Hence, trop., a deep calm, profound tranquillity: ludi sunt, tranquillum est, alcedonia sunt circum forum, Plaut. Cas. prol. 26: mare ipsum aiunt, ubi alcedonia sint, fieri feriatum, Front. Fer. Alc. 3.