A dull, persistent pain in a part of your body.
From Old English 'acan,' related to words meaning 'to cause pain,' possibly connected to Sanskrit 'anj' meaning 'to anoint' (because people would rub aching areas).
Your 'heartache' isn't actually your heart hurting, but we use the same word for emotional pain as physical pain—it's fascinating that emotions literally feel like they're located in our bodies.
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