A person with an outstanding intellect. Synonyms as genius, intellect, author, planner, bright.
To plan a difficult activity, often a crime, in detail and make certain that it happens successfully.
A person who supplies the directing or creative intelligence for a project. If you mastermind a difficult or complicated activity, you plan it in detail.
A person with an outstanding intellect. A mastermind is a brilliant thinker with original ideas. You might be a chess mastermind or a criminal mastermind.
To plan and direct (a usually complex project or activity), especially skillfully. Someone who plans and organizes a complicated activity.