Elder
Old English ieldra, eldra, of Germanic origin; related to German älter, also to eld and old.
wiktionary
From Middle English eldre, from Old English eldra, yldra, ieldra, from Proto-Germanic *alþizô. The vowel change from a to e triggered by the following i is called umlaut or I-mutation.
Perhaps from Proto-Germanic *aliþro(“udder”), from *alaną(“to nourish”). Cognate with dialectal Dutch elder(“udder”). [2]
etymonline
elder (adj.)
"more old," Old English (Mercian) eldra, comparative of eald, ald (see old); only English survival of umlaut in comparison. Superseded by older since 16c. Elder statesman (1921) originally was a translation of Japanese genro (plural).
elder (n.1)
"elderly person, senior citizen," c. 1200, from Old English eldra "older person, parent; ancestor; chief, prince" (used in biblical translation for Greek presbyter); see elder (adj.). Meaning "one having authority in the community" (originally through age) s from late 14c. and biblical translations of Latin seniores. Compare German Eltern, Danish forældre, Swedish föräldrar "parents." The Old English for "grandfather" was ealdfæder. Related: Elders. Middle English also had olderes "parents, forebears" (mid-15c.), from the later form of eld.
elder (n.2)
type of berry tree, c. 1400, from earlier ellen, from Old English ellæn, ellærn "elderberry tree," origin unknown, perhaps related to alder, which at any rate might be the source of the unetymological -d-. Common Germanic, cognates: Old Saxon elora, Middle Low German elre, Old High German elira, German Eller, Erle. Related: Elderberry.
