The antonyms for the word "most increscent" are "decreasing", "reducing", "diminishing", "declining", "weakening", "lessening", and "shrinking." These words depict a small or gradual decrease in something. If something is most increscent, it signifies that it is growing or increasing at a rapid pace. However, the mentioned antonyms carry the opposite meaning, which suggests the decline or reduction in something. For instance, if we talk about the economy, increasing economic growth is good for any country, and decreasing economic growth might cause a problem for the country. Similarly, many things like population, interest rate, inflation, etc., have an increscent and decreasing side.