- dim (adj.)
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- Old English dimm "dark, gloomy, obscure," from Proto-Germanic *dimbaz (source also of Old Norse dimmr, Old Frisian dim, Old High German timber "dark, black, somber"). Not known outside Germanic. Slang sense of "stupid" is from 1892. Related: Dimly; dimness.
- dim (v.)
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- c. 1200, perhaps in Old English, from dim (adj.). Related: Dimmed; dimming.