Source : Webster's Revised Unabridged Dictionary (1913)

Hyades \Hy"a*des\, Hyads \Hy"ads\, n.pl. [L. Hyades, Gr. ?.]
   (Astron.)
   A cluster of five stars in the face of the constellation
   Taurus, supposed by the ancients to indicate the coming of
   rainy weather when they rose with the sun.

         Thro' scudding drifts the rainy Hyaned Vext the dim
         sea.                                     --Tennyson.

Source : WordNet®

Hyades
     n : (Greek mythology) 7 daughters of Atlas and half-sisters of
         the Pleiades; they nurtured the infant Dionysus and Zeus
         placed them among the stars as a reward