/plee"euh deez', pluy"-/ , n.pl.
1. Class. Myth. seven daughters of Atlas and half sisters of the Hyades, placed among the stars to save them from the pursuit of Orion. One of them (the Lost Pleiad ) hides, either from grief or shame.
2. Astron. a conspicuous group or cluster of stars in the constellation Taurus, commonly spoken of as seven, though only six are visible.
[ 1350-1400; ME Pliades Pliades Pleíades (sing. Pleías ); akin to pleîn to sail ]