What is the meaning of Halcyon?

A kingfisher whose nesting by the sea was said, in classical mythology, to cause the Gods to restrain the wind and waves.

1. The dead body of such a bird, said in Tudor times to act as a weather vane when hung from a beam.

The dead body of such a bird, said in Tudor times to act as a weather vane when hung from a beam.

A tropical kingfisher of the genus Halcyon, such as the sacred kingfisher (Halcyon sancta) of Australia.

Pertaining to the halcyon or kingfisher.

Calm, undisturbed, peaceful, serene.

↑ Jespersen, Otto (1909), A Modern English Grammar on Historical Principles (Sammlung germanischer Elementar- und Handbücher; 9)‎, volume I: Sounds and Spellings, London: George Allen & Unwin, published 1961, § 12.22, page 342.

The halcyon; kingfisher.

Source: wiktionary.org