Plural of blight; diseases or conditions that damage plants, or metaphorical ruinations of plans or happiness.
From Middle English 'blight,' possibly from Old Norse 'bligr' (pale/weak) or imitative of withering; agricultural term generalized to any form of ruin.
Agricultural terminology saturates English—'blight,' 'plague,' 'pestilence' all started as crop diseases before becoming metaphors for any disaster, showing how farming shaped human language.
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