Fully grown is a term used to describe something that has reached its full size or maturity. It can be used to describe both living and non-living things. The crossword solutions for the term fully grown are MATURE (6 letters), ADULT (5 letters) and RIPE (4 letters). MATURE refers to something that has reached a certain level of development, while ADULT implies that something has reached the age of majority. RIPE is used to describe something that has reached its peak of perfection. All three words can be used to describe something that is fully grown.