The definition of a pop-up is a window that comes up on top of another window on a computer screen.(noun)
An example of a pop-up is an unwanted window that comes up on a computer screen trying to sell a weight loss pill.
A pop-up is defined as a three-dimensional design in a book that lifts up on the page when the book is opened to the specially-designed page, or a temporary retail store.(adjective)
See pop-up in Webster's New World College Dictionary
See pop-up in American Heritage Dictionary 4
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