Third person singular present tense of flabbergast; to shock or amaze someone greatly.
From the verb flabbergast, with standard -s ending for third person singular present tense in English.
Most people only know the past tense 'flabbergasted,' but when you use 'flabbergasts' in present tense, like 'the magic trick flabbergasts the audience,' it reminds us that flabbergast is genuinely a verb, not just an adjective.
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