cdr
cdr is a built-in function in `C source code'.
(cdr LIST)
Return the cdr of LIST.  If arg is nil, return nil.
Error if arg is not nil and not a cons cell.  See also `cdr-safe'.
See Info node `(elisp)Cons Cells' for a discussion of related basic
Lisp concepts such as cdr, car, cons cell and list.