pop-up

Noun pop-up has 2 senses

• pop-up(n = noun.communication) pop-up book - a book (usually for children) that contains one or more pages such that a three-dimensional structure rises up when a page is opened;
is a kind of book

• pop-up(n = noun.act) pop fly, pop-fly - a short high fly ball;
is a kind of fly, fly ball