In phonology

Phonology

Phonology is, broadly speaking, the subdiscipline of linguistics concerned with the sounds of language. That is, it is the systematic use of sound to encode meaning in any spoken human language, or the field of linguistics studying this use...

, absolute neutralisation is a phenomenon in which a segment of the underlying representation

Underlying representation

In some models of phonology as well as morphophonology, the underlying representation or underlying form of a word or morpheme is the abstract form the word or morpheme is postulated to have before any phonological rules have applied to it. If more rules apply to the same form, they can apply...

 of a morpheme

Morpheme

In linguistics, a morpheme is the smallest semantically meaningful unit in a language. The field of study dedicated to morphemes is called morphology. A morpheme is not identical to a word, and the principal difference between the two is that a morpheme may or may not stand alone, whereas a word,...

 is not realized in any of its phonetic representation

Phonetic representation

Phonetic representation, or more commonly phonetic transcription is the representation of speech sounds using symbols in phonetic alphabet such as IPA, X-SAMPA, Kirshenbaum for linguistic studies and for learning the pronunciation of languages...

. For example, Chomsky & Halle (1968) assume that the underlying representation of the word ellipse contains a final segment /e/ even though this segment is never pronounced. But the assumption of this segment in underlying representation explains the exceptional stress pattern of the word, i.e. that of trisyllabic words instead of that of bisyllabic words, i.e. /ellípse/ instead of /éllipse/. The segment /e/ is deleted after the assignment of stress: thus the opposition between /e/ and zero (the absence of a segment) is neutralized (see also: contextual neutralization).