The opposite of "more loosened" can be "more tightened" or "less loosened." When something is loosened, it becomes less tight, constricted, or restrained. Hence, the antonym for this phrase would mean the opposite- making something tighter or restrict it more. For instance, a knot that is more loosened can be less tied to the point of cutting it completely. Contrarily, when a knot is further tightened, it becomes more secure, solid, and less likely to unravel. Similarly, when dealing with zippers, a zipper that is more loosened may mean it is struggling to hold fast, while tightening it would secure it thoroughly. Therefore, knowing the antonyms for words can help in understanding the core meaning and context of the entire phrase.