Class. Myth.
twin sons of Leda and brothers of Helen, famous for their fraternal affection and regarded as the protectors of persons at sea.
Also, Kastor and Pollux.
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Castor and Pollux,
1. the twin sons of Zeus; Dioscuri.
2. a) the constellation Gemini. b) its two brightest stars.
3. double balls of light due to a discharge of atmospheric electricity; St. Elmo's fire.
Useful english dictionary. 2012.