Yes, span is a Scrabble word!

Verb

1. To cover or extend over an area or time period

Noun

1. The complete duration of something

2. The distance or interval between two points

3. Two items of the same kind

4. A unit of length based on the width of the expanded human hand (usually taken as 9 inches)

5. A structure that allows people or vehicles to cross an obstacle such as a river or canal or railway etc.

6. The act of sitting or standing astride