unbeknownst

Unbeknownst is an adverb that means without the knowledge of someone. It is typically used in phrases like "unbeknownst to him" or "unbeknownst to them" to indicate that an action or event occurred without the awareness of a particular person or group of people. The word is derived from the Old English "uncnawan," meaning "to not know."

The phrase "unbeknownst to" is often used to create a sense of surprise or dramatic irony in storytelling. It can also be used in everyday conversation to explain a situation where someone was unaware of something that was happening. For example, "The cat, unbeknownst to its owner, had been secretly practicing its operatic scales."

While "unbeknownst to" is a common and accepted phrase, some style guides suggest that "unknown to" is a more concise and perhaps more formal alternative. However, "unbeknownst" carries a slightly different nuance, often implying a more active or deliberate lack of awareness on the part of the subject, or a more pronounced surprise for the reader or listener. The word itself can also be used without "to," though this is less common. For instance, "The changes were made, unbeknownst." In this usage, it functions similarly to "secretly" or "covertly."