milliwatt: meaning, definition, pronunciation and examples
C1/TechnicalTechnical, Scientific, Engineering
Quick answer
What does “milliwatt” mean?
A unit of power equal to one thousandth of a watt.
Audio
Pronunciation
Definition
Meaning and Definition
A unit of power equal to one thousandth of a watt.
A metric unit used to measure small amounts of power, especially in electronics, telecommunications, and laser technology. It indicates a very low power level, often associated with signal strength, low-energy devices, or precise power control.
Dialectal Variation
British vs American Usage
Differences
No significant difference in meaning or usage. Spelling and pronunciation are consistent. Contexts of use (e.g., laser specifications, RF engineering) are identical in both variants.
Connotations
Neutral and precise. Implies measurement, calibration, or specification of low power levels.
Frequency
Equally low-frequency in general discourse but standard within relevant technical fields in both regions.
Grammar
How to Use “milliwatt” in a Sentence
[Number] milliwatt(s) of [noun (e.g., power, output)]The [device] has an output of [number] milliwatts.It consumes/emits [number] milliwatts.Vocabulary
Collocations
Examples
Examples of “milliwatt” in a Sentence
noun
British English
- The laser pointer is Class 2, limited to one milliwatt of output power.
- The sensor is so efficient it runs on just a few milliwatts.
- The regulation specifies a maximum permissible exposure of five milliwatts per square centimetre.
American English
- The circuit's power consumption dropped into the milliwatt range.
- Check the datasheet for the optical output in milliwatts.
- This RF module transmits at a mere fifty milliwatts to save battery.
Usage
Meaning in Context
Business
Rare, except in technical product specifications or datasheets (e.g., 'This fibre optic transceiver operates at 10 milliwatts').
Academic
Common in physics, engineering, and electronics textbooks and research papers dealing with low-power systems, lasers, or signal processing.
Everyday
Virtually never used. A layperson would say 'a tiny amount of power' or 'a fraction of a watt'.
Technical
The primary domain. Used in specifications for lasers, LEDs, radio transmitters, receivers, sensors, and low-power electronic circuits.
Watch out
Common Mistakes When Using “milliwatt”
- Misspelling as 'milliwat' (dropping a 't').
- Confusing it with 'millivolt' (a unit of voltage).
- Incorrect pluralisation: 'milliwatt' (singular and plural are often used identically in technical writing, though 'milliwatts' is correct for plural).
FAQ
Frequently Asked Questions
No, it is a technical term primarily used in engineering, physics, and electronics. It is uncommon in everyday conversation.
The standard abbreviation is 'mW', where 'm' stands for 'milli-' and 'W' for 'watt'.
A watt is one thousand times larger than a milliwatt. There are 1000 milliwatts in one watt.
Yes. While rooted in electrical engineering, it is used for any form of power measurement, including optical power (lasers, LEDs), acoustic power (in some contexts), and mechanical power at very small scales.
A unit of power equal to one thousandth of a watt.
Milliwatt is usually technical, scientific, engineering in register.
Milliwatt: in British English it is pronounced /ˈmɪlɪwɒt/, and in American English it is pronounced /ˈmɪliˌwɑːt/. Tap the audio buttons above to hear it.
Learning
Memory Aids
Mnemonic
Think of a MILLIpede with a thousand legs; a MILLIwatt is a watt divided by a thousand.
Conceptual Metaphor
POWER IS A MEASURABLE SUBSTANCE (e.g., 'deliver milliwatts of power', 'a stream of photons carrying milliwatts').
Practice
Quiz
In which context would the term 'milliwatt' be MOST appropriately used?