From HomoExcelsior

1. To make slender, fine, or small. 2. To reduce in force, value, amount, or degree; weaken. 3. To lessen the density of; rarefy. 4. To make (bacteria or viruses) less virulent. 5. To reduce (the amplitude of an electrical signal) with little or no distortion. 6. To become thin, weak, or fine. 7. Reduced or weakened, as in strength, value, or virulence. 8. Gradually tapering to a slender point.

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