Impossible to separate or divide; things or people so closely connected that they cannot be parted.
From Latin 'in-' (not) and 'separabilis' (able to be separated). The root 'separare' means to sever or part.
When two close friends are called 'inseparable,' it literally means they're stuck together like they've been glued—the word evolved from the idea of something physically impossible to pull apart.
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