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Classic usage
Reading level: hard
Estimated CEFR level: B2 — Upper-Intermediate
Estimated from word frequency; not an official CEFR classification.
From Middle English disturbaunce, from Old French destorbance, destourbance, from destourber (“disturb”), from Latin disturbō. By surface analysis, disturb + -ance.
perturbation
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tap / space
Classic usage
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