WordNet sense 1 (in a natural state; not tamed or domesticated or cultivated):

untamed, wild

WordNet sense 2 ((of farmland) not plowed):

unploughed, unplowed

WordNet sense 3 (having undisturbed continuity):

uninterrupted

WordNet sense 4 (uninterrupted in space; having no gaps or breaks):

solid

WordNet sense 5 ((especially of promises or contracts) not violated or disregarded):

kept