The Wiki name for an R-value.
A term coined by ChristopherStrachey in his 1967 paper entitled FundamentalConceptsInProgrammingLanguages. A RightValue is a value that can be stored in a LeftValue.
It is so called because it makes up the right hand side of an assignment expression. For example, in Pascal-like syntax:
lvalue := rvalue
The paper is available online at http://www.kluweronline.com/article.asp?PIPS=257993.