‘Ajam is the name of a maqam

Arabic maqam

Arabic maqām is the system of melodic modes used in traditional Arabic music, which is mainly melodic. The word maqam in Arabic means place, location or rank. The Arabic maqam is a melody type...

 (musical mode) in Arabic, Turkish, and related systems of music. Ajam (عجم) in this usage means "Persian."

The maqam Ajam is constructed of two Ajam trichords with "whole step-whole step" pitch intervals and spacing similar to the 1-2-3 (or 5-6-7) scale degrees found in an equal-tempered Western major scale

Major scale

In music theory, the major scale or Ionian scale is one of the diatonic scales. It is made up of seven distinct notes, plus an eighth which duplicates the first an octave higher. In solfege these notes correspond to the syllables "Do, Re, Mi, Fa, Sol, La, Ti/Si, ", the "Do" in the parenthesis at...

(although the Ajam trichord's third scale degree may be tuned just slightly flat of an equal-tempered third). Because most uses of these Ajam trichords place the next (fourth) scale step a halfstep above the last (third) scale step of the Ajam trichord, the result is essentially the same as the "wholestep-wholestep-halfstep" tetrachord construction of the Western major scale, and thus the maqam Ajam sounds generally the same as the major scale in Western music.

On F (notated C in Turkish music), Ajam is known as Jaharkah.