Defendabilities refer to the ability to justify or defend a particular action or decision. However, there are antonyms or opposite words which denote the lack of this ability. Some possible antonyms for defendabilities could be vulnerability, weakness, insecurity, faultiness, indefensibility, and unsoundness. These words suggest that there is a flaw in the argument or decision that cannot be reasonably defended. Alternatively, inadequate, incompetent, and ungainly may also be antonyms for defendabilities as they describe a situation where an individual or organization lacks the skills, knowledge or resources to justify their decision or judgment. Understanding these antonyms can help individuals weigh both sides of an argument or decision, ensuring that they make informed and defendable choices.