Is it farther or further?
1909, formed in English from Greek geras, geros "old age" (from PIE root *gere- "to grow old" (see gerontology) + iatrikos "of a physician," from iatros (see -iatric).
geriatric ger·i·at·ric (jěr'ē-āt'rĭk)adj.
Of or relating to geriatrics.
Of or relating to old age or to the aging process.