1. Greek Mythology The five daughters of Atlas and sisters of the Pleiades, placed by Zeus among the stars.
2. A cluster of stars in the constellation Taurus, the five brightest of which form a V, supposed by ancient astronomers to indicate rain when they rose with the sun.
[Latin, from Greek Huades, probably from hūs, pig; see sū- in the Appendix of Indo-European roots.]
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