igh

igh is a common English orthographic sequence consisting of the letters i, g, h in that order. It is most recognizable for signaling the long I sound in many English words, especially those that end in -ight. In everyday usage, the sequence appears in high, light, night, sight, might, right, tight, flight, bright and similar words, where the letters gh are no longer pronounced as a separate sound in modern speech.

Phonologically, the core function of igh is to indicate the long vowel sound in many monosyllabic and multisyllabic words. The typical pattern gives an /aɪ/ sound as in high or night. In words with the -ght ending, the gh is usually silent, and the preceding i (or sometimes e as part of a larger digraph) carries the long vowel. There are exceptions and related patterns, such as words containing the larger sequence eigh, where the overall vowel can be /eɪ/ (as in weight or sleigh) or /aɪ/ depending on the word.

Origins and usage: the gh in English has a history rooted in Middle English, where gh represented a voiceless fricative in earlier stages of the language. In modern English, this sound is generally not pronounced, and gh serves primarily a spelling function to preserve historical forms and to indicate the long vowel in related words. The igh sequence is productive in forming a wide set of words across major word classes, especially in the common -ight family. Overall, igh is best understood as a spelling convention that signals a long vowel sound, with gh often being silent in contemporary pronunciation.