One of the last Kings of Gondor, who worked during his short reign to build closer ties with the northern Dúnedain of Arthedain. He died, with both his sons, at the hands of invading Wainriders. The loss of Ondoher and his heirs threw Gondor into a political crisis.
The date of Ondoher's birth appears only in The History of Middle-earth volume XII, The Peoples of Middle-earth. It cannot therefore be considered completely reliable.
Ondoher's name is linguistically connected with that of his country of Gondor (which means 'land of stone'). It is conceivable, therefore, that while Ondoher literally means 'stone lord', it may be intended as 'lord of (the land of) stone'; that is, King of Gondor.