Stumble;
A verb (used without object) [stum·bled, stum·bling.]
1. to strike the foot against something, as in walking or running, so as to stagger or fall; trip.
2. to walk or go unsteadily: to stumble down a dark passage.
3. to make a slip, mistake, or blunder, especially a sinful one: to stumble over a question; to stumble and fall from grace.
