MONOPHONIC
mono, monophonic, single-channel
(adjective) designating sound transmission or recording or reproduction over a single channel
monophonic
(adjective) consisting of a single melodic line
Source: WordNet® 3.1
Etymology
Adjective
monophonic
(of sound reproduction) having a single channel; monaural (compare stereophonic)
(music) having a single melodic line and no harmony (compare polyphonic)
(orthography) having simple one-to-one mapping between letters and phonemes
Source: Wiktionary
Mon`o*phon"ic, a. Etym: [Mono- + Gr. (Mus.)
Definition: Single-voiced; having but one part; as, a monophonic
composition; -- opposed to Ant: polyphonic.
Source: Webster’s Unabridged Dictionary 1913 Edition