allomorfja

Allomorfja is the linguistic study of allomorphy, the phenomenon by which a single morpheme has multiple phonetic realizations, or allomorphs. The surface form of a morpheme is determined by context rather than by meaning alone, so related words can share a morpheme that surfaces differently. Allomorfja covers conditioned allomorphy, where the environment dictates the form, as well as cases where a morpheme is not overtly pronounced in some contexts (zero allomorphy) or where apparent irregularity arises from historical change.

Conditions for allomorphy include phonological context (neighboring sounds, syllable structure), morphosyntactic context (tense, number, case), and lexical factors. Some languages exhibit stem- or dialect-specific allomorphs. In some analyses, there is also free variation, where a morpheme can surface in more than one form without a predictable rule, though strict allomorphy theories typically treat such variation separately.

Examples illustrate the concept. In English, the plural morpheme has three common allomorphs: /s/ after voiceless consonants, /z/ after voiced consonants, and /ɪz/ or /əz/ after sibilants. The past-tense morpheme -ed is pronounced /t/, /d/, or /ɪd/ depending on the final sound of the verb. In Turkish, suffixes like -lar/-ler exhibit vowel harmony, selecting a form that matches the preceding vowels. Some languages also show zero allomorphy, where a tense or number marker is present in the underlying representation but not pronounced in certain contexts.

Allomorfja is a common source of irregularity in languages and often reflects historical sound changes, analogy, and contact. It interacts with orthography, phonology, and syntax, and can vary across dialects and stages of a language. See also allomorphy and morphophonology.