n.1. The extent or measure of space between two points or extremities, as of a bridge or roof; the breadth.
2. The distance between the tips of the wings of an airplane.
3. The section between two abutments or piers of a bridge.
4. Something, such as a railroad trestle or bridge, that extends from one point to another.
5. The distance from the tip of the thumb to the tip of the little finger when the hand is fully extended, formerly used as a unit of measure equal to about 9 inches (23 centimeters).
6. A period of time: a span of life.
tr.v. spanned,
span·ning,
spans 1. To extend across in space or time: a bridge that spans the gorge; a career that spanned 40 years.
2. To encircle or cover with the hand or hands.
3. To measure in spans.