stemvowel

Stemvowel, sometimes written stem-vowel, is a linguistic term referring to the vowel that forms part of a word’s stem and that can vary across related inflected forms. In languages with stem alternations, the stem vowel is not fixed but participates in systematic vowel changes that can signal grammatical information such as tense, aspect, mood, or class.

In Germanic languages, stem vowels are well known through ablaut in strong verbs. Examples include sing, sang, sung and ring, rang, rung, where the stem vowel shifts among i, a, and u across present, past, and participle forms. Such stem-vowel alternations are a key feature of irregular verb paradigms and other word-formation processes.

In other language families, stem vowels can appear as part of patterned vocalism that marks different stems or binyanim. For instance, in some Semitic languages, verb stems are built from roots with specific vowel patterns, and the vowels within the stem help encode voice, aspect, or other grammatical categories, alongside the consonantal root.

Distinctions are important: the stem vowel is different from suffix vowels that attach to the end of a word, and it is also separate from the consonantal root or base consonants. The concept aids historical and comparative linguistics by describing how vowels within the stem participate in inflectional or derivational processes, and it has applications in computational morphology and lexical research. Related concepts include ablaut, vowel harmony, and root-and-pattern morphology.