Find the incorrect word in the following: "She has seen him nearly every days this week."

The word "days" is incorrect in this context because it should be in the singular form "day." The phrase "nearly every day" is the proper expression used to indicate that something has occurred almost each day in a given timeframe. Using "days" incorrectly suggests multiple days, which contradicts the intended meaning of the phrase that refers to the frequency of occurrences throughout the week. Therefore, the correct phrase is "nearly every day," accurately conveying that the action happened on almost every single day of that week.