Eldest
Eldest is a word in English that functions as both an adjective and, less commonly, a noun. It denotes the most advanced in age within a group, and when applied to people it typically refers to the first-born child in a family: the eldest son or the eldest daughter. In everyday speech, English speakers may say oldest to express the same idea; eldest is more common in British English and in formal or historical contexts.
Etymology: Eldest derives from the Old English eld, meaning old, with the superlative suffix -est. The form
Usage and social implications: In many cultures and historical systems, the eldest child has been accorded
Examples: The eldest child may be responsible for elder care, or the oldest sibling may coordinate family