alpha; A, α +

(Greek: ; beginning, first of anything; first letter of the Greek alphabet; used in physics and chemistry to designate a variety of series or values)

1. A set of letters, usually listed in a fixed order, used in writing a language and representing its basic speech sounds; such as, the Cyrillic alphabet.
2. A set of symbols representing units used in communication; especially, speech sounds or words.

Word History

Just as English-speaking people refer to their A B C's, using the first three letters to mean the complete list, as a whole, so the Greeks used alpha and beta, their names for "a" and "b", the first two letters. The combination of these two, alpha + beta, is the origin of the English word alphabet.

—From Picturesque Word Origins; published by G & C. Merriam Company;
Springfield, Massachusetts; 1933; page 14.
Someone who is learning his or her alphabet, or the mere rudiments of any subject; a beginner; an abecedarian.

Also, someone who studies alphabets.

1. Arranged or listed in the customary order of the letters of the alphabet.
2. Based on, typical of, or relating to an alphabet.
In an alphabetic manner or in the customary order of the letters "a" to "z".
Putting something in alphabetical order (customary order of the letters from "a" to "z").
alphabetize (verb), alphabetizes; alphabetized; alphabetizing
1. To arrange articles according to the writing system with a, b, c, d, etc.: Mrs. Smart alphabetized her recipes so that she could find the one she wanted more easily and quickly.
2. To furnish with a system of signals or signs as being equivalent to letters: Some languages, as the Chinese or Japanese, use a method of radical-and-strokes to define or to alphabetize the ordering of the symbols.
alphabetologist (s) (noun), alphabetologists (pl)
Someone who studies the science of letters of a language, arranged in the order fixed by custom, and the system of characters or symbols representing sounds or things.
alphabetology (s) (noun), alphabetologies (pl)
The study or science of character sets that include letters which are used to write languages.
alphanumeric (adjective) (not comparable)
Consisting of or using letters (characters A to Z, lowercase and uppercase), numbers (0 to 9), punctuation marks, and mathematical and other conventional symbols: There are alphanumeric codes and then there are also alphanumeric computers that have alphanumeric keyboards.
alphanumerical (adjective), more alphanumerical, most alphanumerical
Of, pertaining to, or referring to alphanumeric characters (letters and numbers): When used with reference to computer input and output, the alphanumerical set usually includes the uppercase and lowercase alphabetic signs (A–Z, a–z), the numeral digits (0–9), and special figures; such as, the symbols $, #, %, &, +, *, and @, plus any mathematical notations and punctuation marks.

While typically the phrase "alphabetic characters" means only English letters, an alphanumerical character set may also include letters from other languages that also use the Roman alphabet; such as, an e with an acute accent (é) or a c with a cedilla (ç).

—Compiled from information located at The Free Dictionary by Farlex
alphanumerics (pl) (noun) (a plural form used as a singular)
Sets that include letters, digits, and punctuation marks: Alphanumerics utilize alphabetic characters (A-Z, a-z); numbers (1, 2, 3, 4, 5, 6, 7, 8. 9, 0); diacritical signs (! , : ; " ?); and other symbols (±, @, #, $, %, &, *, +, ?, ~, /, \).
alpha-rhythm, alpha-wave
In electroencephalography, rhythmic oscillations in electric potential occurring at an average rate of 10 per second.
1. A virus transmitted by mosquitoes that can cause fever, muscle and joint pain, a rash, and occasionally encephalitis.
2. A genus of viruses of the family Togaviridae (family of viruses that cause Western and Eastern equine encephalitis), including eastern, western, and Venezuelan equine encephalomyelitis viruses, and others that cause dengue-like illnesses in parts of Africa.
analphabetic (adjective), more analphabetic, most analphabetic
A reference to the inability to read or to write: Mrs. Nelson was concerned about the analphabetic state of some of her students and so she created special lessons for them.

You can see all of the letters of the Greek Alphabet on this page.