The term 'early stage' can be broken down into three crossword solutions: EMBRYO (6 letters), INFANCY (7 letters), and ONSET (5 letters). An EMBRYO is the earliest stage of development in a fetus, typically occurring within the first 8 weeks of pregnancy. INFANCY is the period of time immediately following birth, usually lasting until the age of two. ONSET is the beginning or start of something, such as a disease or illness. All three of these terms refer to the early stages of something, whether it be a life, a disease, or another process.