The Collaborative International Dictionary of English v.0.48:

Equidistant \E`qui*dis"tant\, a. [L. aequidistans, -antis;
   aequus equal + distans distant: cf. F. ['e]quidistant.]
   Being at an equal distance from the same point or thing. --
   E`qui*dis"tant*ly, adv. --Sir T. Browne.
   [1913 Webster]