delimiters. In historical linguistics, phonological change is any sound change that alters the distribution of phonemes in a language. In other words, a language In historical linguistics, phonological change is any sound change that alters the distribution of phonemes in a language. In other words, a language develops a new system of oppositions among its phonemes. Old contrasts may disappear, new ones may emerge, or they may simply be rearranged. Sound change may be an impetus for changes in the phonological structures of a language (and likewise, phonol In historical linguistics, phonological change is any sound change that alters the distribution of phonemes in a language. In other words, a language develops a new system of oppositions among its phonemes. Old contrasts may disappear, new ones may emerge, or they may simply be rearranged. Sound change may be an impetus for changes in the phonological structures of a language (and likewise, phonological change may sway the process of sound change). One process of phonological change is rephonemicization, in which the distribution of phonemes changes by either addition of new phonemes or a reorganization of existing phonemes. Mergers and splits are types of rephonemicization and are discussed further below. In historical linguistics, phonological change is any sound change that alters the distribution of phonemes in a language. In other words, a language develops a new system of oppositions among its phonemes. Old contrasts may disappear, new ones may emerge, or they may simply be rearranged. Sound change may be an impetus for changes in the phonological structures of a language (and likewise, phonological change may sway the process of sound change). One process of phonological change is rephonemicization, in which the distribution of phonemes changes by either addition of new phonemes or a reorganization of existing phonemes. Mergers and splits are types of rephonemicization and are discussed further below. Note 1: this split is easily recoverable by internal reconstruction because it results in alternations whose conditions are transparent. Thus Bund "bunch" (as of keys) /bʊnt/ has a plural Bünde /ˈbʏndə/ in contrast to bunt "colorful" with /t/ in all environments (feminine /ˈbʊntə/, neuter /ˈbʊntəs/ and so on). In a neutralizing environment, such as a voiceless stop in word-final position, one cannot tell which of two possibilities was the original sound. The choice is resolved if the corresponding segment can be found in a non-neutralizing position, as when a suffix follows. Accordingly, a non-inflected form like und /ʔʊnt/ "and" is historically opaque (though as the spelling hints, the /t/ was originally */d/). Note 2: unlike most phonological changes, this one became a "surface" rule in German, so loan-words whose source had a voiced stop in the devoicing environment are taken into German with a voiceless one instead: Klub "club" (association) /klʊp/ from English club. The same goes for truncated forms: Bub (for formal Bube "boy") is /buːp/. Note 2a: the surface alternation is what allows modern German orthography to write stops morphophonemically, thus Leib "loaf", Hand "hand", Weg "way", all with voiceless final stops in the simplex form and in compounds, but /b d g/ in inflected forms. In Old High and Middle High German, all voiceless stops were written as pronounced: hleip, hant, uuec and so on. Note 3: the same distribution holds for /s/ vs. /z/, but it arose by a completely different process, the voicing of original */s/ between vowels: *mūs "mouse" > Maus /maʊs/, *mūsīz "mice" (for earlier *mūsiz) > Mäuse /ˈmɔʏzə/. Original long (now short) ss does not voice medially, as in küssen "to kiss" /ˈkʏsen/, nor does /s/ from Proto-West-Germanic *t, as in Wasser "water" /ˈvasɐ/, Fässer "kegs" /ˈfɛsɐ/ plural of Fass /fas/ (= English vat), müßig "idle" /ˈmyːsɪç/. German /ʃ/, as in Fisch "fish", reflects original *sk (in native words) and does not become voiced in any environment: Fischer "fisherman" Note 1: unlike the French example, there is no chance of recovering the historical source of the alternations in English between /s θ f/ and /z ð v/ merely through inspection of the modern forms. The conditioning factor (original location of the voiced alternants between vowels, for example) is quite lost and the investigator has little reason even to suspect the original state of affairs; and anyway the original distributions have been much disturbed by analogical leveling. Worthy and (in some dialects) greasy have voiced fricative (next to the voiceless ones in worth and grease) but adjectives in -y otherwise do not alternate: bossy, glassy, leafy, earthy, breathy, saucy, etc (cf. glaze, leaves, breathe, and note that even in dialects with /z/ in greasy, the verb to grease always has /s/). Note 2: the phoneme /ʃ/ does not alternate with /ʒ/ (and never did). In native words, /ʃ/ is from *sk, and either the change of this sequence to /ʃ/ postdated the rearranging of voicing in pre-Old English fricatives, or else it was phonetically long between vowels, originally, much like the /ʃ/ of present-day Italian (pesce "fish" is phonetically [peʃːe]); and long fricatives, just like sequences of fricatives, were always voiceless in Old English, as in cyssan "to kiss". The Early Modern English development of /ʃ/ < */sj/, as in nation, mission, assure, long postdated the period when fricatives became voiced between vowels. Note 3: a common misstatement of cases like OE /f/ > Modern English /f, v/ is that a "new phoneme" has been created. Not so. A new contrast has been created. Both NE /f/ and /v/ are new phonemes, differing in phonetic specifications and distribution from OE /f/. Without doubt, one component in this misunderstanding is the orthography. If, instead of speaking of the development of Old English /f/ we said that OE /ɰ/ split into /f/ and /v/ there would presumably be less confused talk of "a" new phoneme arising in the process.