rocket scientist
noun /ˈrɒkɪt saɪəntɪst/
/ˈrɑːkɪt saɪəntɪst/
used especially in negative sentences (informal)- an extremely intelligent person
- You don't need to be a rocket scientist to figure out that this plan will not work.
- He's a nice kid—maybe not a rocket scientist, but he's very sweet.