Pegasus, startled, struck a rock with his hoof, creating the spring Hippocrene on Mount Helicon.
[5] The name pegasides (plural form of the Greek feminine adjective pegasis) literally means "originating from or linked with Pegasus".
[6] Hence, in poetry, the waters and streams of Hippocrene and other springs that arose from the hoofprints of Pegasus are called pegasides.
[6][3] Nymphs in general, if associated with springs and brooks, may be called pegasides:[9] thus pegasis, the singular form, is applied by the Roman poet Ovid as a by-name or adjective to the nymph Oenone, daughter of the river-god Cebrenus.
[10][2] Pegasis is used by the Greek author Quintus Smyrnaeus as the name of a nymph who had sex with the Trojan prince Emathion and gave birth beside the river Granicus to Atymnius.