The term 'growthy' is quite specific and can be associated with an increase in a particular aspect or quality. Some synonyms for 'growthy' that can be used to describe a significant or rapid increase may include terms like flourishing, thriving, prospering, progressing, expanding, or developing. Other terms that can be used to describe a gradual increase or expansion may include words like cumulative, incremental, gradual, or steady. Regardless of the context, there are many words that can be used instead of 'growthy,' depending on the specific connotation and degree of the increase or expansion that you wish to describe.