1) Genus hyracotherium 2) Mammal genus 
Hyracotherium (m {respell|HY|rək-o|THEER|ee-əm}; `hyrax-like beast`) is an extinct genus of very small (about 60 cm in length) perissodactyl ungulates which was found in the London Clay formation. This small, dog-sized animal was once considered to be the earliest known member of Equidae before the type species, H. leporinum, was reclassified .....
Hyracotherium is the genus of the earliest-known horse. Another name for this genus is Eohippus meaning dawn horse). This tiny horse dates from the early Eocene Epoch and lived in the Northern hemisphere. It was about 2 feet (60 cm) long and 9 inches (23 cm) high at the shoulder (the size of a small dog!). It had 4 hoofed toes on each front foot an...
[n] - extinct horse genus
genus Hyracotherium noun extinct horse genus; formerly called eohippus