automatic (adj.)

A term used in LINGUISTICS to refer to a MORPHOLOGICAL variation which is motivated by the PHONOLOGICAL rules of a language. For example, the ALTERNATION of /-S/, /-Z/ and /-IZ/ in English PLURALS, POSSESSIVES and VERBS is automatically determined by the phonology: forms ending in a SIBILANT are followed by /-Iz/; non-sibilant VOICELESS CONSONANTS are followed by /-s/; and non-sibilant voiced consonants are followed by /-z/. More complex automatic alternations are illustrated by SANDHI phenomena.