halcyon (adj.)

"calm, quiet, peaceful," 1540s, in halcyon dayes (translating Latin alcyonei dies, Greek alkyonides hemerai), 14 days of calm weather at the winter solstice, when a mythical bird (also identified with the kingfisher) was said to breed in a nest floating on calm seas. The name of this fabulous bird is attested in Middle English as alcioun (late 14c.).

The name is from Latin halcyon, alcyon, from Greek halkyon, variant (perhaps a misspelling) of alkyon "kingfisher," a word of unknown origin. The explanation that this is from hals "sea; salt" (see halo-) + kyon "conceiving," present participle of kyein "to conceive," literally "to swell" (see cumulus) probably is ancient folk-etymology to explain a loan-word from a non-Indo-European language. Identified in mythology with Halcyone, daughter of Aeolus, who when widowed threw herself into the sea and became a kingfisher.

updated on December 10, 2016

Definitions of halcyon from WordNet
halcyon (adj.)
idyllically calm and peaceful; suggesting happy tranquillity;
a halcyon atmosphere
halcyon (adj.)
marked by peace and prosperity;
the halcyon days of the clipper trade
Synonyms: golden / prosperous
halcyon (n.)
a mythical bird said to breed at the time of the winter solstice in a nest floating on the sea and to have the power of calming the winds and waves;
Halcyon (n.)
(Greek mythology) a woman who was turned into a kingfisher;
Synonyms: Alcyone
Halcyon (n.)
a large kingfisher widely distributed in warmer parts of the Old World;
Synonyms: genus Halcyon
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