| 1. | any abnormal phenomenon or product or unusual object; anomaly; aberration. |
| 2. | a person or animal on exhibition as an example of a strange deviation from nature; monster. |
| 3. | a sudden and apparently causeless change or turn of events, the mind, etc.; an apparently capricious notion, occurrence, etc.: That kind of sudden storm is a freak. |
| 4. | Numismatics. an imperfect coin, undetected at the mint and put into circulation. |
| 5. | Philately. a stamp differing from others of the same printing because of creases, dirty engraving plates, etc. Compare error (def. 8), variety (def. 8). |
| 6. | Slang.
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| 7. | Archaic. capriciousness; whimsicality. |
| 8. | unusual; odd; irregular: a freak epidemic. |
| 9. | to become or make frightened, nervous, or wildly excited: The loud noise caused the horse to freak. |
| 10. | freak out, Slang.
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freak (out)
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freak (so) out
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freak out
Experience or cause to experience hallucinations, paranoia, or other frightening feelings as a result of taking a mind-altering drug. For example, They were freaking out on LSD or some other drug. [Slang; mid-1960s]
Behave or cause to behave irrationally and uncontrollably, with enthusiasm, excitement, fear, or madness. For example, The band's wild playing made the audience freak out, or It was such a close accident, it really freaked me out, or She freaked out and ended up in the psychiatric ward. [Slang; 1960s] Also see flip one's lid; wig out.