backquote

Backquote (`) is special syntax in Common Lisp, Scheme, and many other Lisp dialects. It is similar to quote (which returns its argument unevaluated), except it permits parts of the form to be evaluated by prefixing them with comma (,) or comma-splice
(@,). Some examples:

• `(a b (+ 1 2)) => (a b (+ 1 2))
• `(a b ,(+ 1 2)) => (a b 3)
• `(a b ,(list 1 2 3)) => (a b (1 2 3))
• `(a b ,@(list 1 2 3)) => (a b 1 2 3)