Source : Webster's Revised Unabridged Dictionary (1913)

Span \Span\, v. t. [imp. & p. p. {Spanned}; p. pr. & vb. n.
   {Spanning}.] [AS. pannan; akin to D. & G. spannen, OHG.
   spannan, Sw. sp["a]nna, Dan. sp[ae]nde, Icel. spenna, and
   perh. to Gr. ? to draw, to drag, L. spatium space. [root]170.
   Cf. {Spin}, v. t., {Space}, {Spasm}.]
   1. To measure by the span of the hand with the fingers
      extended, or with the fingers encompassing the object; as,
      to span a space or distance; to span a cylinder.

            My right hand hath spanned the heavens. --Isa.
                                                  xiviii. 13.

   2. To reach from one side of to the order; to stretch over as
      an arch.

            The rivers were spanned by arches of solid masonry.
                                                  --prescott.

   3. To fetter, as a horse; to hobble.

Source : WordNet®

span
     n 1: the complete duration of something; "the job was finished in
          the span of an hour"
     2: the distance or interval between two points
     3: two items of the same kind [syn: {couple}, {pair}, {twosome},
         {twain}, {brace}, {yoke}, {couplet}, {distich}, {duo}, {duet},
         {dyad}, {duad}]
     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. [syn: {bridge}]
     6: the act of sitting or standing astride [syn: {straddle}]
     [also: {spanning}, {spanned}]

span
     v : to cover or extend over an area or time period; "Rivers
         traverse the valley floor", "The parking lot spans 3
         acres"; "The novel spans three centuries" [syn: {cross},
         {traverse}, {sweep}]
     [also: {spanning}, {spanned}]

spanned
     See {span}