Berenice's hair, in Astronomy, a modern constellation of the northern hemisphere, composed of unformed stars, between the Lion's tail and Bootes. This constellation is said to have been formed by Conon, an astronomer, in order to console the queen of Ptolemy Euergetes for the loss of a lock of her hair, which was stolen out of the temple of Venus, where she had dedicated it on account of a victory obtained by her husband.