STEM

STEM, also theme. A term in GRAMMAR and WORD-FORMATION for a ROOT plus the element that fits it into the flow of language. Stems are basic to such inflected languages as Latin and rare in analytic languages like English. In Latin, the root am (love) and a thematic vowel -a- make up the stem ama-, to which appropriate inflections are added: -s in amas thou lovest, -t in amat he/she/it loves. The only stems in present-day English are acquisitions from Latin and Greek. Such stems have no syntactic role, but often decide the spelling and sometimes the pronunciation of derivatives: because negative and auditory derive from Latin negare to deny, audire to listen, their stems are negat- and audit-. Spellings like *negitive and *audatory are therefore not possible. Whereas the rhythm of Latin makes the quality and quantity of all stem vowels clear, the rhythm of English often does not do so, reducing the vowels to a schwa and therefore limiting sound–spelling correspondences. See THEMATIC VOWEL.