3-D printer

"3-D" means "three-dimensional".
A "3-D" movie is a movie where you wear special glasses, and it looks like objects are coming out of the movie screen towards your face.
A "3-D" printer is a new invention that can make objects out of plastic, or metal, or other materials, even food:

http://www.youtube.com/watch?v=FVOVOe89TZ4