Synonyms of eldest

1 Syllable
gray
2 Syllables
hoary, tired, grizzled, oldish, senior, first-born, firstborn, fossil, wasted, versed, aged, olden, ancient, older, skilled, infirm
3 Syllables
veteran, senile, elderly, gray-haired, impaired, exhausted, geriatric, seasoned, mature, decrepit, enfeebled, matured
4 Syllables
experienced, inactive, venerable
5 Syllables
debilitated, superannuated