any anonymous function that you create using the @code{lambda} macro
or the @code{function} special form or the @code{#'} syntax
(@pxref{Anonymous Functions}), is automatically converted into a
-closure.
+@dfn{closure}.
+@cindex closure
A closure is a function that also carries a record of the lexical
environment that existed when the function was defined. When it is
invoked, any lexical variable references within its definition use the