@c NJFIXME explain [env]
@deffn {Scheme Procedure} defined? sym [env]
-@deffnx {C Function} scm_definedp (sym, env)
+@deffnx {C Function} scm_defined_p (sym, env)
Return @code{#t} if @var{sym} is defined in the lexical environment @var{env}. When @var{env} is not specified, look in the top-level environment as defined by the current module.
@end deffn