The process of fire consuming something, releasing heat and light; something very hot or intense; a strong desire or feeling.
From Old English 'byrnan' and 'birnan,' from Proto-Germanic roots. The word has meant both the physical act of combustion and metaphorically an intense emotion since Old English times.
The phrase 'burning question' isn't random—burning was historically the most intense human experience, so people used it metaphorically for urgency and passion, making it one of the most powerful metaphors in any language.
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