char-name character ⇒  name
Returns a string that is the name of the character, or nil if the character has no name.
All non-graphic characters are required to have names unless they have some implementation-defined attribute which is not null. Whether or not other characters have names is implementation-dependent.
The standard characters
<Newline> and <Space> have the respective names "Newline" and "Space".
The semi-standard characters
<Tab>, <Page>, <Rubout>, <Linefeed>, <Return>, and <Backspace> 
(if they are supported by the implementation)
have the respective names
"Tab",  "Page",  "Rubout",  "Linefeed",  "Return", and "Backspace"
(in the indicated case, even though name lookup by "#\" 
and by the function name-char is not case sensitive).
 (char-name #\ ) ⇒  "Space"
 (char-name #\Space) ⇒  "Space"
 (char-name #\Page) ⇒  "Page"
 (char-name #\a)
⇒  NIL
OR⇒ "LOWERCASE-a"
OR⇒ "Small-A"
OR⇒ "LA01"
 (char-name #\A)
⇒  NIL
OR⇒ "UPPERCASE-A"
OR⇒ "Capital-A"
OR⇒ "LA02"
 ;; Even though its CHAR-NAME can vary, #\A prints as #\A
 (prin1-to-string (read-from-string (format nil "#\\~A" (or (char-name #\A) "A"))))
⇒  "#\\A"
Should signal an error of type type-error if character is not a character.
Non-graphic
characters having names are written by the Lisp printer
as "#\" followed by the their name; see Printing Characters.