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(Or "drop-down menu", "pop-down menu") A menu in a graphical user interface, whose title is normally visible but whose contents are revealed only when the user activates it, normally by pressing the mouse button while the pointer is over the title, whereupon the menu items appear below the title. The user may then select an item from the menu or click elsewhere, in either case the menu contents are hidden again. A menu item is selected either by dragging the mouse from the menu title to the item and releasing or by clicking the title and then the item.
When a pull-down menu appears in the main area of a window, as opposed to the menu bar, it may have a small, downward-pointing triangle to the right.
Compare: scrollable list.