What is definition of halycon?

The term "halcyon" or "halcyon days" is derived from Greek mythology. According to the myth, Alcyone (sometimes spelled Halcyon), the daughter of Aeolus, the god of the wind, was married to Ceyx, the king of Thessaly. Zeus became angry with the couple because Ceyx had offended him, so he transformed himself into a bird of prey and sank Ceyx's ship, causing his death. Alcyone was so grief-stricken that she threw herself into the sea. Out of compassion, the gods transformed both Alcyone and Ceyx into kingfishers. The birds were allowed to breed in peace during a period of seven days, known as the "halcyon days," which coincided with the winter solstice. During this time, the seas were calm and the winds were still, allowing the birds to nest and hatch their eggs in safety.

Today, the term "halcyon" is used to describe a period of peace, prosperity, or happiness. It is often used in reference to a particular time or place that is regarded as a period of idyllic tranquility. It can also be used to describe a person or thing that brings calm or joy. The term "halcyon days" is still used to refer to a period of calm or good fortune.