Understand at Last is a phrase that can be used to describe the feeling of finally comprehending something after a long period of confusion or difficulty. The term can be broken down into two parts: Understand and At Last. The crossword solution for Understand is GRASP, which means to take hold of something with one's hands or to comprehend something intellectually. At Last is a phrase that implies finality, meaning that the understanding has been achieved after a long period of time.