Up-surged is a word that means to increase, rise or grow rapidly. Antonyms or opposites for up-surged could include declined, decreased, diminished or dropped. These words denote a reduction or decrease in something. For instance, if the sales of a company have declined or decreased, it means that it has decreased from the previous year. Similarly, if the temperature has dropped, it indicates a decrease in temperature. It is important to have a good understanding of antonyms as they can effectively convey the opposite meaning of a word, thereby adding more color and depth to your language usage.