A nervous reaction is a physical or emotional response to a stressful situation. It can be characterized by a feeling of fear, anxiety, or panic. The two crossword solutions for this term are TIC and COLDSWEAT. TIC is an abbreviation for a type of involuntary muscle movement or spasm, which is often associated with nervous reactions. COLDSWEAT is a phrase used to describe the physical sensation of sweating due to fear or anxiety. Both of these terms are commonly used to describe a nervous reaction.