The Collaborative International Dictionary of English v.0.48:
Inspan \In*span"\, v. t. & i. [D. inspannen.] To yoke or harness, as oxen to a vehicle. [South Africa] [1913 Webster]WordNet (r) 3.0 (2006):
inspan v 1: attach a yoke or harness to; "inspan the draft animals" [ant: outspan]