'Al Hakefak'(על הכיפאק) is a common Israeli slang word (taken from Arabic) which means "great" or "Awesome!"

It is pronounced "Al ha'kefak" and in context can be used as follows: Question: "How is life?" Answer: "Al ha'kefak!" If you want to be very expressive, you can even add, "Al hakef kef kefak!"