The term 'Stage After Zygote' refers to the stage of development that follows the zygote, which is the single-celled organism formed when a sperm and egg fuse. The answer to the crossword puzzle is 'EMBRYO, ' which is the stage of development that follows the zygote and precedes the fetus. During the embryonic stage, the cells of the zygote divide and differentiate into the various organs and tissues of the body.