Nicholas Bielby offers an introductory glossary.
Blending: the smooth transition from one phoneme to another in pronunciation, enabling the reader to run the individual letter sounds together to make a recognisable word, for example,"cat" ' cat (not cuh-a-tuh). Note: Oblique marks are used here to identify sounds, inverted commas to identify the written form.
Consonant: the letters and letter sounds that aren't vowels. Compared with vowels, their sound-values are relatively reliable. Some are prolonged consonants (m, n, l, s, f, v) which can be pronounced without adding a vowel sound, but the rest cannot. So, you tend to say cuh for "c", puh for "p", creating a problem for blending in phonics teaching.
Consonant blends: the combination of consonant sounds before or after a vowel, for example, "bl-" and "-nds" in "blends". It is often hard for children to distinguish and separate out (or segment) the different consonant sounds in blends, so a child may well spell "pram" "pam" or "plant" "plat".
Decoding: the writing system is a way of encoding pronunciations. Hence, "decoding" is translating written words into speech sounds using the phonic rules of the code.
Digraph: a combination of two letters to represent one phoneme, for example, ch, sh, th, ee, oa, ng, and so on. (Note: "th" can represent two different phonemes as in though and through).
Grapheme: the written (alphabetic) representation of a phoneme. Thus "grapheme" consists of the graphemes g, r, a, ph, e - e and m. Digraphs are one sort of grapheme.
Graphophonics: concerns the relationships between spelling patterns and sound patterns. A term that may be used in preference to "phonics" meaning (1) below, to avoid confusion with meaning (2).
Onset: the part of a syllable that precedes the vowel. For example, amp has no onset, but the onset of stamp is st.
Phoneme: the smallest unit of sound that is used to distinguish between words. There are 44 phonemes in the English language. For example, the first phonemes in bin and pin are very close to each other in sound and children sometimes mistake them, but they constitute distinct phonemes in English because they distinguish between words.
Phonics: (1) the relationship between the sounds and written form of a language; (2) a system of teaching reading by training in the sounding out of letters and blending these sounds to identify words.
Phonology: the study of the sound systems within a language used to distinguish between words.
Phonological awareness: reflective alertness to the constituent sounds within words, e.g. shown in recognising and producing rhymes, counting the syllables or the phonemes within a word.
Rime: within a syllable, the vowel sound and any consonant sounds that follow it. For example, ow is the rime in "how", and ound is the rime in "sound". Clearly it is rimes that rhyme.
Segment: Noun: a constituent sound element within a word, for example, a syllable, onset, rime or phoneme. Verb: to separate out segments in a word, for example, to identify the three syllables in elephant or the four phonemes in fox.
Syllable: the segment of a word centred on a single vowel sound, together with any attached consonants, whether coming before or after the vowel.
Vowel: the 20 vowel sounds of English are related to the alphabetic vowels a, e, i, o and u (and sometimes y) and their combinations. A vowel is the pulse of vocal energy at the centre of a syllable.