The adjective elder is not a synonym for elderly. In comparisons between two persons, elder means "older" but not necessarily "old": My elder sister is sixteen; my younger, twelve. (Eldest is used when three or more persons are compared: He is the eldest of four brothers.) In other contexts elder does denote relatively advanced age but with the added component of respect for a person's achievement, as in an elder statesman. If age alone is to be expressed, one should use older or elderly rather than elder: A survey of older Americans; an elderly waiter. � Unlike elder and its related forms, the adjectives old, older, and oldest are applied to things as well as to persons.
An elder statesman is an older person who is respected and asked for advice because of their past experience.
Your elders and betters old-fashioned - people who are older than you and who should be treated with respect.
Elders are generally any learned or authoritative figures in religious traditions.
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