The word "un clad" refers to something that is not covered or protected. Its antonyms, therefore, would be words that mean the opposite: covered, protected, or dressed. Some possible antonyms for "un clad" could be clad, covered, wrapped, shielded, clothed, armored, guarded, sheltered, or fortified. These words imply a sense of safety, protection, or comfort, which is the opposite of the insecurity or exposure that goes along with being "un clad." Depending on the context in which the word is used, other antonyms may be appropriate as well, such as hidden, concealed, disguised, or veiled.