What does disassimilation mean?
Disassimilation is a technical term from linguistics describing a sound change in which one of two similar or identical sounds in a word becomes noticeably different from its neighbour. Speakers naturally find strings of repeated or near-identical sounds awkward to pronounce, so over generations languages tend to alter one of them — for example, a sequence of two r-sounds may come to be pronounced with an l instead. This process is essentially the mirror image of assimilation, in which adjacent sounds grow more alike, and it accounts for many irregularities learners notice between older written forms and modern pronunciations. In biology, the word is occasionally extended to describe the breakdown of complex substances into simpler ones within an organism, the reverse of assimilation. Disassimilation is chiefly found in academic contexts — historical linguistics, phonetics, and philology — and is closely related to, though less frequently used than, the term 'dissimilation', with which it largely overlaps in meaning.
nounThe process by which two sounds that are alike or identical in a word become less similar to each other, typically as a result of phonetic change over time. More broadly in biology and physiology, it can refer to the breakdown of complex substances into simpler ones within an organism.
- (Linguistics) A phonetic or phonological change in which one of two similar or identical sounds in a word becomes less like the other.
- (Biology, rare) The breakdown of complex substances into simpler ones within a living organism, contrasted with assimilation.
"In the history of English, disassimilation caused the two r-sounds in 'marble' to diverge, with one shifting to an l."
"Latin 'peregrinus' underwent disassimilation in Old French, yielding 'pèlerin', from which English derives the word 'pilgrim'."
"In historical linguistics seminars, students often cite consonant disassimilation as evidence that speakers unconsciously favour articulatory ease."
The plural refers to multiple instances or types of this sound-change process, usually in scholarly discussion.
"The chapter catalogues several disassimilations attested across Romance languages."
It's the reason 'marble' doesn't sound the way it's spelled — when two identical sounds sit too close together, language quietly pushes them apart.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of disassimilation
Disassimilation is formed from the Latin-derived prefix 'dis-', indicating separation or reversal, combined with 'assimilation', which traces back to Latin 'assimulare', meaning 'to make similar', from 'ad-' ('to') plus 'simulare' ('to make like'), ultimately rooted in 'similis' ('like, resembling'). The term was coined in the nineteenth century alongside related terms in comparative and historical linguistics, when scholars sought precise labels for systematic sound changes across Indo-European languages. It shares this Latin ancestry with words such as 'similar', 'simulate', and 'assimilate'.
Related word forms
How disassimilation is actually used
A technical term used chiefly in historical linguistics, phonetics, and philology; it is rare outside academic writing. Some scholars use 'disassimilation' and 'dissimilation' interchangeably, though 'dissimilation' is considerably more common in modern linguistic literature.
Easily confused with disassimilation
Dissimilation is the standard linguistic term for the same sound-change process; 'disassimilation' is a rarer variant, while the shared prefix 'dis-' can mislead readers into thinking they denote opposite processes.
Assimilation is the opposite process, in which neighbouring sounds become more alike rather than less alike.