Renewable Energy

Regular expression, in computer science, a string that describes or matches a set of strings, according to certain syntax rules

Resident Evil (series), a franchise of horror-adventure video games, developed by Capcom

Rhenium, the chemical symbol for the element

Real estate

Réaumur scale degree (°Ré)

Royal Engineers, a corps of the British Army

Réunion, .re being its Internet country code top-level domain (ccTLD)

Ra, an ancient Egyptian god/deity (alternate spelling)

Requirements engineering during the development of computer programs

The second pitch of the solfege scale, corresponding to the note 'D'

Reverse engineering, the process of taking something (a device, an electrical component, a software program, etc.) apart and analyzing its workings in detail

Reynolds number, in physics

Recursively enumerable set

Île de Ré, an island off the Charente-Maritime département of France

Rupee, a currency

Aer Arann, IATA code

Giovanni Battista Cardinal Re, an Italian priest

Religious Education

Re (album), by the Mexican band Café Tacuba

Re (VB), a village in the Italian province of Verbano Cusio Ossola

Re{z} or <math>\Re</math>: the real part in mathematics

Re, Norway, a municipality

RE (complexity), the set of recursively enumerable languages

A romanisation of the Japanese kana れ and レ

Relative effectiveness factor, a measurement of an explosive's power

Re is an exclamation in Greek. RE, the acronym, may mean:

Royal Society of Painter-Etchers and Engravers, since 1991 the Royal Society of Painter-Printmakers

The Latin expression re, meaning in the matter of or by the thing, à la in re. The use of Latin re, in the sense of about, concerning, is English usage.

Reinsurance, as in Swiss Re or Fortress Re