The term 'grew back' can be defined as REGENERATED, which is an 11 letter word. This term is used to describe the process of something that has been damaged or lost being restored to its original state. It can refer to physical objects, such as a broken bone healing, or a plant regrowing after being cut down. It can also refer to intangible things, such as a relationship being repaired after a disagreement. In any case, the term 'grew back' is used to describe the process of something being restored to its original state.