To extend through the distance between or across.
The suspension bridge spanned the canyon.
To extend through (a time period).
The novel spans three centuries.
To measure by the span of the hand with the fingers extended, or with the fingers encompassing the object.
to span a space or distance; to span a cylinder
To generate an entire space by means of linear combinations.
To be matched, as horses.
To fetter, as a horse; to hobble.
The process by which something is spanned.