In biology, the very first stage of cell division is known as prophase. During prophase, the cell prepares itself in various ways for the division that occurs in later stages.
If you take a biology class, you'll learn all about mitosis, when cells divide and duplicate their DNA. This process takes place over five phases, the first of which is prophase. During prophase, the nucleolus and nuclear membrane break down, and chromosomes coil more tightly. This is all in preparation for when the cell splits into two daughter cells. The word comes from Greek roots meaning "before stage."