J
Abbreviation with 3 meanings
| Stands for | Joule |
|---|---|
| Meanings | 3 |
| Categories | Units & Measurements, Law & Legal, Texting & Internet Slang |
| Also written | /j, J. |
J has three meanings. The most common are Joule (engineering unit) and Judge or Justice (court); it can also stand for Joking (tone indicator).
Meanings of J at a glance
| # | J stands for | Context |
|---|---|---|
| 1 | Joule | Units & Measurements › Engineering Unit |
| 2 | Judge or Justice | Law & Legal › Court |
| 3 | Joking (tone indicator) | Texting & Internet Slang › Social Media |
1. Joule
Units & Measurements · Engineering Unit Abbreviations
The SI unit of energy, work and heat: the work done by a force of one newton over one meter, or one watt for one second. Food energy, battery capacity, explosive energy and physics problems are expressed in joules and their multiples.
Example: Lifting a 1 kg book by 1 m against gravity takes about 9.8 J.
English physicist James Prescott Joule, whose experiments in the 1840s showed that mechanical work and heat are equivalent, gave the unit its name. One food Calorie equals 4,184 J and one kWh equals 3.6 million J. Surge protectors are rated in joules for the energy they can absorb before failing.
2. Judge or Justice (J.)
Law & Legal · Court Abbreviations
Title placed after a judge's surname in opinions, case reports and citations to identify who wrote an opinion, as in "Kagan, J., dissenting". In English and Commonwealth practice it follows the name of a High Court judge, so "Smith J" is read aloud as "Mr Justice Smith".
Example: Scalia, J., dissenting, warned that the majority's new test would prove unworkable.
The plural is JJ., and a chief judge or chief justice is C.J. British usage drops the full stop. In prose, use the full title before the name ("Justice Kagan", "Judge Posner"); in Bluebook citations the author appears in a parenthetical only when relevant, such as "(Sotomayor, J., concurring)".
3. Joking (tone indicator) (/j)
Texting & Internet Slang · Social Media Abbreviations
Tone tag placed at the end of a message to show that it is a joke and should not be taken seriously. Used on Tumblr, X, Discord, TikTok comments and in group chats.
Example: I'm moving to Antarctica to avoid my group project /j
One of the most widely used tone indicators. The system spread on Tumblr and Twitter around 2020, partly through neurodivergent users who find tone hard to read in plain text. Some people find tone tags unnecessary or patronizing, while others value the clarity they add.
Related abbreviations
More engineering unit abbreviations
- Hz – Hertz
- in-lb – Inch-pound
- inH2O – Inches of water column
- inHg – Inches of mercury
- K – Kelvin
- kcal – Kilocalorie
- kgf – Kilogram-force
- kHz – Kilohertz
See all 103 engineering unit abbreviations →
More court abbreviations
- FPD – Federal public defender
- ICC – International Criminal Court
- ICJ – International Court of Justice
- IJ – Immigration judge
- JJ. – Judges or Justices
- JP – Justice of the peace
- JPML – Judicial Panel on Multidistrict Litigation
- JSC – Justice of the Supreme Court
See all 87 court abbreviations →
This entry is for general education and is not legal advice. Abbreviation use varies between institutions; always confirm in context.