A splinter or small pointed piece of wood or bone that sticks into the skin; a prickly fragment.
From Old English 'æstell' or Germanic origin, possibly related to Old High German 'astel.' The word has cognates in various Germanic languages all referring to sharp, piercing fragments or splinters.
This is a wonderfully specific medieval word for something everyone experiences—that annoying splinter you get from a wooden porch—yet modern English just borrowed 'splinter' from Dutch instead of keeping this older Germanic term.
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