Related Clues:

• Small spasmodic reaction
• Quirky habit
• Muscle jerk
• Nervous mannerism
• Start of a grid-based game
• Opening in "Hollywood Squares," essentially
• "___-Tac-Dough" (quiz show)
• First X, potentially
• ___ Tac (breath freshener)
• "Twitch," minus every other letter
• Nervous twinge
• First O, maybe
• Opening in "Hollywood Squares"
• Involuntary muscle movement
• Contraction of a sort