alpha(redirected from alpha (alpha) lower motor neuron)
Also found in: Thesaurus, Medical, Financial, Encyclopedia.
1. The first letter of the Greek alphabet. See Table at alphabet.
2. The first of a series; the beginning.
3. Astronomy The brightest star in a constellation.
a. The mathematical estimate of the return on a security when the return on the market as a whole is zero. Alpha is derived from a in the formula Ri = a + bRm, which measures the return on a security (Ri) for a given return on the market (Rm) where b is beta.
b. The return on an investment portfolio that can be attributed to the skill of the portfolio's manager rather than the performance of the market.
1. Being the highest ranked or most dominant individual of one's sex. Used of social animals: the alpha female of the wolf pack.
a. Being in the first position relative to a designated carbon atom in an organic molecule at which an atom or a group may be substituted.
b. Referring to the first of a group of isomers, or molecules of similar origin or properties, determined arbitrarily by those who discover or classify them. Used in combination: alpha-tocopherol.
1. (Letters of the Alphabet (Foreign)) the first letter in the Greek alphabet (Α, α), a vowel transliterated as a
2. (Education) Brit the highest grade or mark, as in an examination
3. (General Physics) (modifier)
a. involving or relating to helium-4 nuclei: an alpha particle.
b. relating to one of two or more allotropes or crystal structures of a solid: alpha iron.
c. relating to one of two or more isomeric forms of a chemical compound, esp one in which a group is attached to the carbon atom to which the principal group is attached
4. (modifier) denoting the dominant person or animal in a group: the alpha male.
[via Latin from Greek, of Phoenician origin; related to Hebrew āleph, literally: ox]
1. (Astronomy) (foll by the genitive case of a specified constellation) usually the brightest star in a constellation: Alpha Centauri.
2. (Communications & Information) communications a code word for the letter a
n., pl. -phas,
1. the first letter of the Greek alphabet (Α, α).
2. the first; beginning.
3. (cap.) the brightest star in a constellation: Alpha Centauri.
4. the first or foremost in a series of related items.adj.
a. (esp. of animals) having the highest rank of its sex in a dominance hierarchy: the alpha female.
b. being the most prominent, talented, or aggressive person in a group: the alpha male of investment bankers.
6. pertaining or linked to the carbon atom closest to a particular group in an organic molecule.
[< Latin < Greek álpha < Semitic; compare aleph]
Switch to new thesaurus
|Noun||1.||alpha - the 1st letter of the Greek alphabet|
Greek alphabet - the alphabet used by ancient Greeks
|2.||alpha - the beginning of a series or sequence; "the Alpha and Omega, the first and the last, the beginning and the end"--Revelations|
start - the beginning of anything; "it was off to a good start"
|Adj.||1.||alpha - first in order of importance; "the alpha male in the group of chimpanzees"; "the alpha star in a constellation is the brightest or main star"|
|2.||alpha - early testing stage of a software or hardware product; "alpha version"|