Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
boreas is a noun meaning "a wind that blows from the north". It carries 2 recorded senses.
a wind that blows from the north
(Greek mythology) the god who personified the north wind
“Boreas was pictured as bearded and powerful and winged and draped against the cold”
Greek mythology
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for boreas come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.