α

Definition from Wiktionary, the free dictionary
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Greek lc alpha.svg
Unicode name GREEK SMALL LETTER ALPHA
Greek and Coptic U+03B1
Greek and Coptic → β

Translingual[edit]

Symbol[edit]

α

  1. (electrodynamics) The fine structure constant.
  2. (classical mechanics) Represents angular acceleration.
    See Wikipedia article on angular acceleration for usage.
  3. (chemistry) Used in chemical nomenclature.
    α-lactam has a three-membered ring structure.
  4. (astronomy) Used to identify the brightest star in a constellation, for instance α-Centauri.
  5. (topology) Alexandroff compactification

Derived terms[edit]

See also[edit]

  • alpha (for names of this symbol in other language)

Greek[edit]

Etymology 1[edit]

Derived from its Ancient Greek majuscule counterpart Α (A, Alpha), in turn from the Phoenician letter 𐤀 (aleph).

Letter[edit]

α (a) (lower case, upper case Α)

  1. Lower-case άλφα (álfa, alpha), the first letter of the modern Greek alphabet. Represents the open front unrounded vowel: IPA(key): /a/.
Usage notes[edit]
  • Ancient Greek, however, did not distinguish between upper case and lower case. See Α (A) for details.
Derived terms[edit]
  • α' (a', one, 1)
  • (,a, one thousand, 1,000)
See also[edit]

Etymology 2[edit]

Interjection[edit]

α! (a!)

  1. ah!, aah! (expressing emotion)