Prefix · one / single
Signals one or uniqueness: monologue, monopoly, monotone, monochrome, monolingual.
Written by Bryan López, English teacher · Updated
Mono- comes from Greek "monos" (alone, single) and signals the presence of a single element or category: monologue = a speech by one person; monopoly = market control by one company; monotone = a single musical note without variation; monorail = a single rail (vs a railway with two rails). The core idea is always "one and only one."
In science, mono- is highly productive: monoxide (one oxygen atom, as in CO, carbon monoxide), monosyllabic (of one syllable), monoculture (farming of a single crop species), monochromatic (of a single wavelength of light). In linguistics, monolingual = speaks only one language (opposite of bilingual or multilingual).
Attaches to nouns and adjectives. Identical in Spanish and English:
Pronunciation: /ˈmɒnəʊ/ in British English, /ˈmɑːnoʊ/ in American English. Identical in Spanish and English.
mono-/ˈmɒnəʊ/
Tap the button to hear how the prefix sounds. Each word in the table has its own audio.
"Monotonous" describes anything repetitive and dull: a monotonous job (no variety), a monotonous voice (no expression), a monotonous landscape. It is not limited to music.
Mono- = one oxygen: carbon monoxide (CO) is the odourless, toxic gas. Di- = two oxygens: carbon dioxide (CO₂) is the gas exhaled by humans and absorbed by plants.
A trick to remember it
Mono- = "one": monologue = one person speaks, monopoly = one company dominates, monochrome = one colour, monolingual = one language. Whenever you see mono- in a word, look for the "single thing" that defines the concept.
Exercise 1 · Form the word
Exercise 2 · Pick the right one
"Carbon ___ is an odourless, colourless gas that is extremely dangerous in enclosed spaces."
Exercise 3 · Pick the right one
What is the difference between "monolingual" and "bilingual"?
The prefix mono- signals one or uniqueness: monologue, monopoly, monotone, monochrome, monolingual. In Spanish it usually maps to mono-.
The prefix mono- is pronounced /ˈmɒnəʊ/. For example, "monologue".
"logue" becomes "monologue". It is a typical example of the mono- prefix.
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