monophonic

From mono- +‎ -phonic. Compare Ancient Greek μονόφωνος (monóphōnos, “with only one voice or tone”)^[1]

• (Received Pronunciation) IPA^(key): /ˌmɒnə(ʊ)ˈfɒnɪk/
• (General American) IPA^(key): /ˌmɑnəˈfɑnɪk/
• Rhymes: -ɒnɪk

monophonic

1. (of sound reproduction) Having a single channel.

   Synonym: monaural

   Coordinate terms: stereophonic, quadraphonic

2. (music) Having a single melodic line and no harmony.

   Synonyms: homophonic, monophonous

   Coordinate term: polyphonic

   Near-synonym: monodic

3. (orthography) Having simple one-to-one mapping between letters and phonemes.
   • 1828 July 7, Peter S. Du Ponceau, “On some Points connected with the Nature of the Chinese Language (enclosure in letter from Basil Hall)”, in The Philosophical magazine, volume 5:

     From a similar selection, says M. Remusat, the Coreans have made a monophonic alphabet of nine vowels and fifteen consonants, with which they write their language.