Poland

wiktionary

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1560s. From Pole +‎ land, from German Pole, singular of Polen, from Polish Polanie(“Poles”, literally “field dwellers”), from Proto-Slavic *poľane, plural of *poľaninъ(“field dweller”), from *poľe(“field”) + *-ěninъ, ultimately from Proto-Indo-European *pleh₂-(“flat, wide”).

etymonline

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Poland (n.)

1560s, from Pole + land (n.). Related: Polander.