The phrase "most impinging" refers to something that has the greatest impact or influence. Its antonym could be "least impinging," meaning something that has the least impact or influence. Other antonyms could be "insignificant," "inconsequential," "unimposing," or "insubstantial," which all describe things that have little to no impact or influence. On the other hand, antonyms for "impinging" could include "avoid," "evade," "neglect," or "ignore," depicting the opposite of the verb's meaning to strike or hit against something forcefully. By knowing these antonyms, we can better understand the concept of "most impinging" and can contrast it with other ideas.