Family name Gerontius (Gareth 
, Geraint , Геронтий 
) , around the world, is quite a rare cognomen. The surname Gerontius is habitual in Ireland, where it is a rare surname, Cameroon, and Hungary. In absolute terms, it is commonest in Indonesia, the United Kingdom, and Spain. Predominantly, Gerontius is the forename as well as the last name.