The word "sterilizable" implies the ability to be made free from all germs, bacteria, and other microorganisms. Its antonyms would, therefore, be words that indicate the opposite meaning. Some of the antonyms for "sterilizable" include "dirty," "unclean," "contaminated," "infected," "unsanitary," "unclear," "impure," "soiled," and "unhealthy." All these words suggest a state where the object or environment is not free from harmful germs or bacteria. It is important to note that in certain contexts, some of these words might be used positively, such as "unclear water," which would mean water that is not contaminated but simply not transparent.