I think you could call this a Pop-Up, You might also see this referred to as a Popover, or Popper. The idea is the user clicks on a button and a modal like window "Pops" up on their screen calling attention for the user to make some type of decision or provide more detailed information than a tooltip.
In your example, I would call this a Pop-up Menu.
From w3Schools on Bootstrap Popover Plugin
The Popover Plugin
The Popover plugin is similar to tooltips; it is a pop-up box that appears when the user clicks on an element. The difference is that the popover can contain much more content.
This is not native to Bootstrap.
I believe the equivalent in Material Design would be called a "Dialog"
Dialogs inform users about a task and can contain critical information, require decisions, or involve multiple tasks.
Apple Human Interface Design
Apple refers to this type of design as Popovers.
A popover is a transient view that appears above other content onscreen when you tap a control or in an area. Typically, a popover includes an arrow pointing to the location from which it emerged. Popovers can be nonmodal or modal. A nonmodal popover is dismissed by tapping another part of the screen or a button on the popover. A modal popover is dismissed by tapping a Cancel or other button on the popover.
Another useful article to read: Pop-up, popover or popper? — a quick look into UI terms