all of a sudden
phrase
variants
or less commonly on a sudden
: very quickly in usually an unexpected way : in a sudden manner
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'All over sudden' vs. 'All of a sudden'
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Cite this Entry
“All of a sudden.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/all%20of%20a%20sudden. Accessed 15 Dec. 2025.
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