letters of (the alphabet)

a traditionalist

letters of the alphabet

vowel, a weak letter or a long vowel (i.e. ا, or و, or ی)

letters of alphabets

lip consonants like the letters P, B etc.

letters of A B J D corresponding to 1234- the first of a series of eight words comprising the letters of the Arabic alphabet in the order in which they were originally disposed (agreeing with that of the Hebrew and Aramaic)