Emily Dickinson Lexicon

CYN'O-SURE, n. [Gr. κυνοσουρα, the tail of the dog, ursa minor, the little bear.]

The constellation near the north pole, consisting of seven stars, four of which are disposed like the four wheels of a chariot, and three lengthwise, like the beam; hence called the chariot or Charles's wain. As seamen are accustomed to steer by this constellation, it is sometimes taken for that which directs or attracts attention. – Encyc. Milton.