alpha conversion

Noun

• One of the three rewrite rules of lambda calculus, in which a bound variable of a lambda term gets replaced by another variable across its entire scope. So if there is a lambda term of the form $(\backslash lambda\; x.\; t)$ and it is desired to have x replaced with y, then the rewritten lambda term would have the form $(\backslash lambda\; y.\; t[y/x])$ where $t[y/x]$, "t with y in stead of x", has had all free instances of x in t replaced with y.