mistakenly

Mistakenly is an adverb that describes an action performed in error or under a false belief. It modifies verbs to indicate that something was done, perceived, or concluded wrongly. It is closely related to phrases like "by mistake," which express a similar idea.

Common uses include stating that an action occurred due to misperception rather than intent, as in "She mistakenly assumed the meeting was today" or "They mistakenly believed the document was complete." The term is versatile and appears in talking about beliefs, identifications, conclusions, and interpretations that turn out to be incorrect.

Etymology and formation: Mistakenly is formed from the adjective mistaken with the adverbial suffix -ly. The adjective mistaken itself derives from the verb to mistake, meaning to misunderstand or to err; the sense of being taken or understood wrongly underlies the meaning of the adverb.

Related terms and notes: The noun form is mistake, and the adjective form is mistaken. The common collocation by mistake is often used interchangeably with mistakenly, depending on sentence structure. A frequent misspelling is mistakedly, while the standard form remains mistakenly. In formal writing, using mistakenly to describe the manner of an action is generally appropriate, whereas by mistake emphasizes the error as the cause of the action.