apply

(apply <proc> <args>) calls with the elements of <args> (a list) as the actual arguments and returns the result of the call.

(apply <proc> <arg1> … <args>) calls with the elements of the list (append (list <arg1> …) <args>) as the actual arguments and returns the result of the call.

Example:

[1] (apply + '(1 2 3))
6
[2] (apply + 1 2 '(3))
6
[3]