Tenacity means holding on with determination and refusing to give up, even when things get difficult. Someone with tenacity keeps trying to solve a hard math problem instead of tossing their pencil aside in frustration. A scientist shows tenacity by running experiment after experiment, learning from each failure until finally discovering what works.

Tenacity is the stubborn persistence to keep working toward a goal despite obstacles and setbacks. A climber shows tenacity by continuing up a mountain despite sore muscles and rough weather. An inventor demonstrates tenacity by building prototype after prototype, refusing to quit when the first dozen versions don't work.

Tenacity differs from mere stubbornness. Stubborn people might refuse to change their minds even when they're wrong, but tenacious people adapt their approach while staying focused on their goal. They're flexible in method but unwavering in purpose.

History celebrates tenacity: Thomas Edison tested thousands of materials before finding one that worked for the light bulb filament. Helen Keller overcame incredible obstacles to learn, communicate, and inspire millions. When you face a challenge that seems impossible, tenacity is what helps you keep going until you reach your goal.