'Major scale' definitions:

Definition of 'major scale'

noun

A diatonic scale with notes separated by whole tones except for the 3rd and 4th and 7th and 8th [syn: major scale, major diatonic scale]

From: GCIDE

Major \Ma"jor\, [L. major, compar. of magnus great: cf. F. majeur. Cf. Master, Mayor, Magnitude, More, a.]
1. Greater in number, quantity, or extent; as, the major part of the assembly; the major part of the revenue; the major part of the territory. [1913 Webster]
2. Of greater dignity; more important. --Shak. [1913 Webster]
3. Of full legal age; adult. [Obs.] [1913 Webster]
4. (Mus.) Greater by a semitone, either in interval or in difference of pitch from another tone. [1913 Webster]
Major key (Mus.), a key in which one and two, two and three, four and five, five and six and seven, make major seconds, and three and four, and seven and eight, make minor seconds.
Major offense (Law), an offense of a greater degree which contains a lesser offense, as murder and robbery include assault.
Major scale (Mus.), the natural diatonic scale, which has semitones between the third and fourth, and seventh and fourth, and seventh and eighth degrees; the scale of the major mode, of which the third is major. See Scale, and Diatonic.
Major second (Mus.), a second between whose tones is a difference in pitch of a step.
Major sixth (Mus.), a sixth of four steps and a half step. In major keys the third and sixth from the key tone are major. Major keys and intervals, as distinguished from minors, are more cheerful.
Major third (Mus.), a third of two steps. [1913 Webster]

From: GCIDE

major diatonic scale \major diatonic scale\ n. (Mus.), The natural diatonic scale, which has semitones between the third and fourth, and seventh and eighth notes, and whole tones between the other notes; the scale of the major mode, of which the third is major; also called major scale. See Scale, and Diatonic. [1913 Webster + WordNet 1.5]