say it: MAH-nuh-tohn
monotone is a noun and adjective meaning "an unchanging intonation". It carries 4 recorded senses.
an unchanging intonation
a single tone repeated with different words or different rhythms (especially in rendering liturgical texts)
of a sequence or function; consistently increasing and never decreasing or consistently decreasing and never increasing in value
mathematics
sounded or spoken in a tone unvarying in pitch
“the owl's faint monotonous hooting”
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for monotone come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.