Past tense of bumble; acted clumsily or confusedly, or spoke in a confused or stammering way.
From 'bumble,' likely originally from 'bum' plus a frequentative suffix, meaning to move around making buzzing or blundering sounds.
You can actually hear the clumsiness in the word itself—'bumbled' has this awkward, tripping-over-itself quality, like it's hard to say without stumbling.
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