monotonic has definitions from the field of mathematics
1
[ adjective ] (mathematics) of a sequence or function; consistently increasing and never decreasing or consistently decreasing and never increasing in value

Synonyms

monotone

2
[ adjective ] sounded or spoken in a tone unvarying in pitch

Synonyms

monotonous monotone

Examples

"the owl's faint monotonous hooting"

Related terms

unmelodious

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