The term "kiss-ass" is often used to describe someone who shows excessive flattery to gain favor or advance their own agenda. However, there are several other synonyms that can be used to express a similar sentiment, including "brown-noser," "bootlicker," "toady," "sycophant," and "apple polisher." These words all describe someone who seeks to win favor with others through insincere displays of admiration or flattery. While these terms can be used in a derogatory manner, it is important to note that individuals may engage in this behavior to succeed in certain settings, such as the workplace or social circles.