Source : WordNet®

undeviating
     adj 1: going directly ahead from one point to another without
            veering or turning aside; "some people see evolution
            as an undeviating upward march from simple organisms
            to the very complex"; "a straight and narrow
            tree-lined road unswerving across the lowlands" [syn:
            {unswerving}]
     2: used of values and principles; not subject to change;
        steady; "undeviating loyalty"