geriatric (adj.)

*gerə-, Proto-Indo-European root meaning "to grow old." It forms all or part of: geriatric; geriatrics; gerontocracy; gerontology.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit jara "old age," jarati "makes frail, causes to age;" Avestan zaurvan "old age;" Greek geron "old man;" Ossetic zarond "old man;" Armenian cer "old, old man."

word-forming element, from Latinized form of Greek iatrikos "healing," from iatros "physician, healer" (related to iatreun "treat medically," and iasthai "heal, treat"); of uncertain origin, perhaps from iaomai "to cure," related to iaino "heat, warm, cheer," probably from a root meaning "enliven, animate."