Confused, agitated, or thrown off balance; made flustered through some disturbance.
Past participle of 'flusterate' (if used as a verb), or possibly a blend/alteration of 'fluster' with '-ated' or '-ered' endings. This form appears in dialectal speech and informal literature.
This is what linguists call a 'folk etymology' product—people hear 'fluster' and intuitively add '-ated' endings because so many English verbs work that way. It's not 'incorrect' so much as it's created through a rule people naturally follow.
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