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Allophony

PHONOLOGY: the phenomenon that a phoneme has different (context-dependent) variants. The different variants are called allophones. EXAMPLE: in English [th] in tin, [?t] in cat and [t] in stop are allophones of the phoneme /t/. Syllable-initially the phoneme is pronounced differently than in medial or in final position. The differences between the allophones can be expressed by phonological rules.