Past tense of 'freak'; to suddenly become very scared, upset, or lose control of your emotions.
From 'freak,' which originally meant a sudden turn or twist of fate, or a whimsical notion. By the 1960s, it came to mean becoming emotionally overwhelmed, especially in counterculture slang.
The word 'freaked' is actually pretty recent slang that went mainstream—it jumped from 1960s youth culture into everyday speech, originally meaning to lose emotional control, but 'freak' itself originally just meant an unexpected turn of fate, so it evolved from 'something weird happened' to 'I'm losing it!'
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