Bourne

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early 16th century (denoting a boundary of a field): from French borne, from Old French bodne (see bound2).

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French bourne, from a- +‎ bourne(“boundary”), from Old French bodne, from Medieval Latin bodina, a word of unknown ultimate origin, but possibly from Proto-Indo-European *bʰudʰmḗn(“bottom, base”), see also Proto-Celtic *bundos. [1]