Prefix · very small / one millionth
Signals extreme smallness or one millionth of a base unit: microscope, microphone, microchip.
Written by Bryan López, English teacher · Updated
Micro- comes from Greek "mikros" (small) and signals extreme smallness or one millionth of a base unit. microscope = an instrument to see very small things; microphone = a device that captures the faintest sounds; microchip = a tiny integrated circuit; microbiology = the study of microscopic organisms. In the International System it abbreviates to µ and means 10⁻⁶ (0.000001).
Micro- is one of the most productive prefixes in scientific and technical language: microwave, microorganism, microbiology, microprocessor, microsurgery. In modern informal use it also signals a smaller version of something: micro-influencer (a smaller-scale influencer), micromanage (control at excessive detail level), microclimate (a local climate pattern).
Attaches to scientific and technical nouns with no spelling change. Identical in Spanish and English:
Pronunciation: /ˈmaɪkrəʊ/, stressed on the first syllable with a schwa at the end. Identical in Spanish and English.
micro-/ˈmaɪkrəʊ/
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The microphone (microphone) converts sound into an electrical signal. The speaker (loudspeaker) amplifies and reproduces that signal. They are separate components that work together.
In the International System, micro- = 10⁻⁶ (micrometres, microseconds). In everyday compounds like microwave, micromanage, micro-influencer, it simply means "very small" or "small-scale." The context determines which sense applies.
A trick to remember it
Micro- = "very small" or "one millionth": microscope = see the very small, microphone = pick up tiny sounds, microchip = a tiny circuit. Any scientific field can take micro- to signal the study of its smallest components: microbiology, microeconomics, microclimate.
Exercise 1 · Form the word
Exercise 2 · Pick the right one
"The lab identified the ___ responsible for the infection using advanced DNA sequencing."
Exercise 3 · Pick the right one
What does "micromanage" mean in a work context?
The prefix micro- signals extreme smallness or one millionth of a base unit: microscope, microphone, microchip. In Spanish it usually maps to micro-.
The prefix micro- is pronounced /ˈmaɪkrəʊ/. For example, "microscope".
"scope" becomes "microscope". It is a typical example of the micro- prefix.
un-, re-, pre-, dis-, over-, in-... every beginning you need to unlock thousands of English words at once.