Related Clues:

• Muscle movement
• First ''O'' of O-O-O
• '-- Tac Dough'
• Cramp
• First correct ''Hollywood Squares'' square
• Start of a winning combination
• Some kind of jerk?
• It can't be helped
• Nervous twitch
• Small spasm
• Nervous reaction
• One X of XXX
• Half a breath mint?
• Common contraction?
• -- -tac-toe