If for some reason when on your Lisp journey you come across an errant symbol and wish to check whether it is a function or not, it can be done with fboundp. This function will return T if the symbol is a function or NIL if it is not.
For an example run the following code within your favourite Lisp environment:
(defun test () "I AM A TEST!")
(fboundp 'test)
(fboundp 'this-symbol-should-hopefully-not-be-a-function)
You should get the following output.
T
NIL
