Re

Re or RE may refer to:

Arts and entertainment

Re, the second syllable of the scale in solfège
- Re, or D (musical note), the second note of the musical scale in fixed do solfège
Re: (band), a musical duo based in Canada and the United States

France (Atlantic margin):
- Île de Ré, off west coast of France
- Le Bois-Plage-en-Ré, commune on Île de Ré
Norway:
- (in Vestfold county): Re, Norway, former municipality
- (in Vestland county): Re, Vestland, village in Gloppen municipality
Italy:
- Re, Piedmont, Italian community
- Torrents (i.e. seasonal streams):
  - Re di Anfo
  - In the Val Camonica:

Effective reproduction number, in epidemiology
Religious education (RE), the study of religion
re (interjection), in Greek
Re (kana), the Japanese syllables written れ and レ
Re (Egyptian religion), an ancient Egyptian god also known as Ra
RE (complexity) (recursively enumerable), a complexity class of decision problems
Regional-Express, a type of regional train in Germany, Luxembourg and Austria
Regular expression, a sequence of characters to match text against a specified pattern
Renewable energy
Resident Evil, popular video game franchise of survival horror
Reverse engineering
Relative effectiveness, or RE factor, an expression of an explosive's demolition power
Reynolds number, a dimensionless quantity in fluid mechanics used to help predict flow patterns
Rhenium, a chemical element with the symbol 'Re'
In re, Latin for 'in the matter of...'
RE: and Re:, used in email subject lines as a shortened form of in re
Royal Engineers, a part of the British Army
Royal Society of Painter-Printmakers, whose fellows may use the Post-nominal letters RE