MW
Abbreviation with 4 meanings
| Stands for | Megawatt |
|---|---|
| Meanings | 4 |
| Categories | Units & Measurements, Science & Engineering, Geography & Places |
| Also written | mW |
MW has four meanings. The most common are Megawatt (engineering unit) and Molecular weight (chemistry); it can also stand for Milliwatt and Malawi.
Meanings of MW at a glance
| # | MW stands for | Context |
|---|---|---|
| 1 | Megawatt | Units & Measurements › Engineering Unit |
| 2 | Molecular weight | Science & Engineering › Chemistry |
| 3 | Milliwatt | Units & Measurements › Engineering Unit |
| 4 | Malawi | Geography & Places › Country Code |
1. Megawatt
Units & Measurements · Engineering Unit Abbreviations
Power plants, wind turbines, data centers and large industrial loads are rated in megawatts, millions of watts. Modern onshore wind turbines are typically rated around 3 to 6 MW, and a large data center can draw 100 MW or more.
Example: The offshore wind farm will have 60 turbines of 15 MW each.
Capacity in MW is not the same as energy produced: a 100 MW solar farm with a 25 percent capacity factor generates about 219,000 MWh a year. Power-plant documents write MWe for electrical and MWt for thermal output. The lowercase mW, a milliwatt, is a billion times smaller.
2. Molecular weight
Science & Engineering · Chemistry Abbreviations
Mass of a molecule relative to one twelfth of a carbon-12 atom, numerically equal to the molar mass in grams per mole. Chemists use MW to convert between grams and moles, and polymer scientists use average molecular weights to describe chain length.
Example: Aspirin has an MW of 180.16, so a 500 mg tablet contains about 2.8 millimoles.
Strictly, IUPAC prefers "relative molecular mass" (symbol Mr), which is dimensionless, while molar mass carries units of g/mol; MW remains common on reagent bottles and in biology. Proteins are usually described in kilodaltons, such as a 66 kDa protein. In power engineering the same letters mean megawatt.
3. Milliwatt (mW)
Units & Measurements · Engineering Unit Abbreviations
One thousandth of a watt, used for laser pointers, radio transmitters, Bluetooth and Wi-Fi output, hearing aids and other low-power electronics.
Example: Class 3R laser pointer, maximum output under 5 mW, 532 nm green beam.
US FDA rules limit laser pointers marketed to consumers to under 5 mW. Radio power is often expressed in dBm, decibels relative to 1 mW: 0 dBm equals 1 mW and 20 dBm equals 100 mW. The capital-M MW (megawatt) is a billion times larger, a mix-up that appears surprisingly often in news copy.
4. Malawi
Geography & Places · Country Code Abbreviations
Landlocked southeast African country with Lilongwe as its capital and MWI as its alpha-3 code. Lake Malawi holds more fish species than any other lake, most of them cichlids found nowhere else.
Example: Tobacco auctions in MW set prices for the country's main export.
Malawi was the British protectorate of Nyasaland until 1964. The kwacha trades as MWK.
Related abbreviations
More engineering unit abbreviations
- MPG – Miles per gallon
- MPGe – Miles per gallon equivalent
- mph – Miles per hour
- mV – Millivolt
- MWh – Megawatt-hour
- Nm – Newton-meter
- NPT – National Pipe Thread
- Pa – Pascal
See all 103 engineering unit abbreviations →