diacritical mark — a mark or sign affixed to a letter to specify the sound it represents in a particular situation.
digraph — a sound written with two letters, such as "ee" and "or."
grapheme — printed form used in correct spelling and books; letter/s that produce one sound relationship.
orthography — 1.) the study or systematic use of standard, proper, or correct spelling of the words in a language; 2.) spelling with complete phonetics; rules for spelling, syllabication and plurals.
phoneme — any one of the smallest, most basic units of sound in a spoken language.
phonemic awareness — the ability to understand the sounds of spoken language, to blend those sounds into spoken words, and to manipulate those sounds.
phonics — 1.) the study of sound; 2.) the method of using the sounds of a language when teaching people to read; 3.) letter-sound correspondences. (See: Theory.)
prefix — a word element placed in front of a word, which changes its meaning. (See: Prefixes and Suffixes.)
suffix — a word element placed at the end of a word, which changes its meaning or function. (See: Prefixes and Suffixes.)