| Ace |
| Whiz |
| Guru |
| Crack |
| Maven |
| Pro-__ |
| Skilful |
| Skillful |
| Dab hand |
| Old hand |
| Masterful |
| Go-to guy |
| __ master |
| Aficionado |
| Authority. |
| Black belt |
| TED talker |
| Specialist |
| Skilled one |
| Crackerjack |
| Know-it-all |
| Master hand |
| Go-to person |
| Knowledgeable |
| Man who knows |
| No dilettante |
| Highly skilled |
| Kind of witness |
| Black belt, say |
| Panelist, often |
| Type of witness |
| Black belt, e.g. |
| Consultant, probably |
| Puzzle-solving level |
| One with the know-how |
| Paid witness, perhaps |
| Authority on a subject |
| Beginner's counterpart |
| Know-nothing's opposite |
| One who knows his stuff |
| One with serious skills |
| Hardest difficulty level, often |
| Crossword puzzle solver with a pen, often |