dim

Etymology 1

From Middle English dim, dym, from Old English dim, dimm (“dim, dark, gloomy; wretched, grievous, sad, unhappy”), from Proto-West Germanic *dimm, from Proto-Germanic *dimmaz (“dark”), from Proto-Indo-European *dʰem- (“to whisk, smoke; obscure”). Compare Faroese dimmur, Icelandic dimmur (“dark”) and dimma (“darkness”).

adj

1. Not bright or colorful.
   The lighting was too dim for me to make out his facial features.
2. (colloquial) Not smart or intelligent.
   He may be a bit dim, but he's not entirely stupid.
3. Indistinct, hazy or unclear.
   His vision grew dimmer as he aged.
4. Disapproving, unfavorable: rarely used outside the phrase take a dim view of.

noun

1. (archaic) Dimness.
   All about me the Red Weed clambered among the ruins, writhing to get above me in the dim. Night, the Mother of Fear and Mystery, was coming upon me. 1898, H.G. Wells, The War of the Worlds, London: William Heinemann, page 278

verb

1. (transitive) To make something less bright.
   He dimmed the lights and put on soft music.
2. (intransitive) To become darker.
   The lights dimmed briefly when the air conditioning was turned on.
3. To render dim, obscure, or dark; to make less bright or distinct
4. To deprive of distinct vision; to hinder from seeing clearly, either by dazzling or clouding the eyes; to darken the senses or understanding of.
   Her starry eyes were dimm'd with streaming tears. 1740, Christopher Pitt, The Aeneid

Etymology 2

adj

1. (music) Clipping of diminished.