The crossword solution for the term DEVELOPING, AFTER 'IN' is UTERO, which is a five-letter word. Utero is the Latin word for womb and is used to refer to the uterus, which is the organ in the female reproductive system where a fetus develops during pregnancy. The uterus is a muscular organ that is lined with a mucous membrane and is responsible for nourishing and protecting the fetus until it is ready to be born.