What are the opposite words for under-development?

Instead of using the term "under-development," there are several antonyms that can be used to describe progress or advancement. These could include terms like growth, development, flourishing or advancing. These words suggest a positive upward momentum and can be used to describe anything from personal growth to the progress of a company or country. Similarly, words like expansion, evolution, mature or prosper can be used to suggest that an area has moved past a state of stagnation and into progress. It's important to use optimistic language and acknowledge the progress that has been made, rather than simply focusing on the negative aspects of a situation.

Antonym of the day

getting way
approve, begin, go.