Having the same boundaries or area; occupying the same space or covering the same region; coinciding in extent or scope.
From co- plus terminus (Latin for boundary) plus '-ous' suffix. More common than coterminal, this word describes things with identical limits or ranges.
India's state of Kerala is almost coterminous with the Malayalam language region—people literally mean 'land where Malayalam is spoken' when they say Kerala, making the political boundary and cultural boundary the same thing.
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