WordNet (r) 3.0 (2006):

nonconvergent
    adj 1: (of lines, planes, or surfaces) never meeting or crossing
           [syn: nonconvergent, nonintersecting]

Moby Thesaurus II by Grady Ward, 1.0:

20 Moby Thesaurus words for "nonconvergent":
   aligned, analogous, coextending, coextensive, collateral,
   concurrent, equal, equidistant, equispaced, even, lined up,
   nondivergent, parallel, parallelepipedal, parallelinervate,
   paralleling, parallelodrome, parallelogrammatic, parallelogrammic,
   parallelotropic