a measure of length, roughly nine inches. Meaning "length of time" first attested 1599; that of "space between abutments of an arch, etc." is from 1725. Meaning "maximum lateral dimension of an aircraft" is first recorded 1909. Attention span is recorded from 1922.
O.E. spannen "to clasp, fasten, stretch, span," from P.Gmc. *spanwanan (cf. O.N. spenna, O.Fris. spanna, M.Du. spannen, O.H.G. spannan, Ger. spannen), from PIE base *(s)pen- "to draw, stretch, spin" (cf. L. pendere "to hang, to cause to hang," pondus "weight" (the weight of a thing measured by how much
it stretches a cord), pensare "to weigh, consider;" Gk. ponein "to toil;" Lith. spendziu "lay a snare;" O.C.S. peti "stretch, strain," pato "fetter," pina "I span;" O.E. spinnan "to spin;" for other cognates, see spin
). The meaning "to encircle with the hand(s)" is from 1781; in the sense of "to form an arch over (something)" it is first recorded 1633. Spanner (1639), the British name for the wrench, is from Ger., originally a tool for winding the spring of a wheel-lock firearm
"two animals driven together," 1769, from Du. span, from spannen "to stretch or yoke," from M.Du. spannen, cognate with O.E. spannen "to join" (see span