The antonyms for "unsafest" would be words that indicate safety or security. Such antonyms could include "secure," "protected," "safe," "sound," "stable," or "guarded." These words are used to describe situations or places where there is no danger or risk to individuals or property. "Safe" is a common antonym for "unsafest" that suggests a state of being free from harm, danger, or injury. To express the opposite of "unsafest," one might say "safest," which implies the highest level of safety and protection. Using these antonyms can help to convey a positive message and a feeling of security in various contexts.