Past tense of harbor; sheltered someone or something, or held onto a feeling or thought.
From Old English 'herebeorgan' meaning 'to shelter,' with '-ed' added for past tense; used both literally for ships and figuratively for emotions since Middle English.
What's clever is how English extended this word from physical protection (harboring a ship) to emotional protection (harboring resentment), showing how our brains understand feelings as things we keep safe inside ourselves.
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