Alternation (linguistics)
In linguistics, an alternation is the phenomenon of a morpheme exhibiting variation in its phonological realization. Each of the various realizations is called an alternant. The variation may be conditioned by the phonological, morphological, and/or syntactic environment in which the morpheme finds itself.
Alternations provide linguists with data that allow them to determine the allophones and allomorphs of a language's phonemes and morphemes and to develop analyses determining the distribution of those allophones and allomorphs.
The term "sound change" refers to diachronic changes, which occur in a language's sound system. On the other hand, "alternation" refers to changes that happen synchronically and do not change the language's underlying system.
Phonologically conditioned alternation
An example of a phonologically conditioned alternation is the English plural marker commonly spelled s or es. This morpheme is pronounced,, or, depending on the nature of the preceding sound.- If the preceding sound is a sibilant consonant, or an affricate, the plural marker takes the form. Examples:
- *mass, plural masses
- *fez, plural fezzes
- *mesh, plural meshes
- *mirage, plural mirages
- *church, plural churches
- *bridge, plural bridges
- Otherwise, if the preceding sound is voiceless, the plural marker takes the likewise voiceless form. Examples:
- *mop, plural mops
- *mat, plural mats
- *pack, plural packs
- *cough, plural coughs
- *myth, plural myths
- Otherwise, the preceding sound is voiced, and the plural marker takes the likewise voiced form.
- *dog, plural dogs
- *glove, plural gloves
- *ram, plural rams
- *doll, plural dolls
- *toe, plural ''toes''
Alternation related to meaning
Morphologically conditioned alternation
has an example of morphologically conditioned alternation. The feminine form of many adjectives ends in a consonant sound that is missing in the masculine form. In spelling, the feminine ends in a silent e, while the masculine ends in a silent consonant letter:- masculine petit, feminine petite
- masculine grand, feminine grande
- masculine gros, feminine grosse
- masculine joyeux, feminine joyeuse
- masculine franc, feminine franche
- masculine bon, feminine bonne
Syntactically conditioned alternation
Syntactically conditioned alternations can be found in the Insular [Celtic languages], where words undergo various initial consonant mutations depending on their syntactic position. For example, in Irish, an adjective undergoes lenition after a feminine singular noun:- unmutated mór , mutated in bean mhór
- unmutated beic "bike", mutated in Prynodd y ddynes feic.