No.
Abbreviation with 4 meanings
| Stands for | Number |
|---|---|
| Meanings | 4 |
| Categories | Writing & Everyday, Geography & Places, Science & Engineering |
| Also written | NO, No, no. |
No. has four meanings. The most common are Number (everyday) and Norway (country code); it can also stand for Normally open and Nobelium.
Meanings of No. at a glance
| # | No. stands for | Context |
|---|---|---|
| 1 | Number | Writing & Everyday › Everyday |
| 2 | Norway | Geography & Places › Country Code |
| 3 | Normally open | Science & Engineering › Electronics & Electrical |
| 4 | Nobelium | Science & Engineering › Chemical Element |
1. Number
Writing & Everyday · Everyday Abbreviations
Precedes a number to identify a position, rank, item or address, as in "No. 1 hit," "No. 10 Downing Street" or "Invoice No. 4471." The abbreviation comes from Latin numero.
Example: The song spent six weeks at No. 1 on the Billboard Hot 100 last summer.
The o is the last letter of Latin numero, "by number." Americans often use the # sign instead, while the numero sign is common in Europe and Russia. AP style uses No. with figures for position or rank ("No. 1 choice") but not in street addresses. The plural is Nos.
2. Norway (NO)
Geography & Places · Country Code Abbreviations
Norway, capital Oslo, alpha-3 NOR, is in the European Economic Area but not the EU. Norwegian IBANs are the shortest in Europe at 15 characters, and the sovereign wealth fund is the world's largest.
Example: Our NO customers are billed in Norwegian kroner.
The Norway problem is a famous programming bug: YAML 1.1 parsers read the unquoted country code NO as the Boolean false. The language codes are no, nb (Bokmål) and nn (Nynorsk).
3. Normally open (NO)
Science & Engineering · Electronics & Electrical Abbreviations
Describes a switch or relay contact that is open, not conducting, at rest and closes when the device is activated, as with a doorbell button or a start push button. NO contacts complete a circuit only while actuated.
Example: The start button uses NO contacts that close only while it is pressed.
Many relays offer both NO and NC contacts sharing a common terminal, known as a changeover or SPDT contact. Pressure, float and limit switches are specified as NO or NC depending on whether they should close or open when triggered. No is also the chemical symbol for nobelium.
4. Nobelium (No)
Science & Engineering · Chemical Element Abbreviations
Nobelium (atomic number 102) is a synthetic actinide whose discovery was contested for decades among laboratories in Sweden, the United States and the Soviet Union. Its longest-lived isotope lasts about an hour, so it is studied atom by atom.
Example: Experiments showed that No, unlike most actinides, prefers the +2 oxidation state in water.
The Nobel Institute of Physics in Stockholm claimed the element in 1957 and proposed naming it after Alfred Nobel, but the result could not be reproduced. Berkeley reported its own synthesis in 1958, and work at Dubna in the Soviet Union in the 1960s was ultimately judged the most reliable. IUPAC credited Dubna in the 1990s but kept the established name nobelium.
Related abbreviations
More everyday abbreviations
- Mgr – Manager
- min – Minimum
- misc. – Miscellaneous
- natl. – National
- NYE – New Year's Eve
- OJ – Orange juice
- OK – All correct (from the joke spelling "oll korrect")
- opp. – Opposite
See all 82 everyday abbreviations →