1. A person who is both sly and cynical at the same time.
2. A person who has the ability to be very smooth and go about doing something so that no one notices.
3. Someone who's moves are calculated & bold to obtain a specific result.
1. Wow, that slynical guy! He calculates his every move and gets away with anything!
2. Anthony carried on with his illegal business for months, convincing everyone it was legitimate. He's so slynical.