Number & MeasureGreek → English
Monotonic
/ˌmɒnəˈtɒnɪk/adjective
Describing a sequence or function that only ever increases or only ever decreases, never doubling back.
The Greek roots
μόνος
mónos
single, alone
τόνος
tónos
pitch, stretching
Literally: “of one pitch”
The story of the word
τόνος comes from τείνω, to stretch, and first meant the tension of a string, then the pitch it sounds. μονότονος in Greek described speech kept at one note, which is still what monotonous means. Mathematics borrowed the picture and dropped the sound: a monotonic function holds one direction the way a drone holds one pitch.
- How it travelled
- Ancient Greek → scientific coinage → English
- First recorded
- 19th century
Same family
monotonoustonetonicisotonic
In a sentence
Because the cost function is monotonic in temperature, the optimum sits at one end of the range.