liminal, alley, channel, course, gap, lane, road, route, shaft, subway, thoroughfare, tunnel, Amid, Among, between, betwixt, borderline, buried , concealed , covert , disguised , embryonic, faint , fringe, halfway, hidden , impalpable , imperceptible , inappreciable , inaudible , in-between, inconspicuous , indistinct , indistinguishable , initial, insensible, insignificant , intangible , interim, intermediate, interstitial, intervening, invisible, line, marginal, midst, obscure , outlying, peripheral, preliminary, shrouded , slender , slight , subtle , trace, transitional, trivial, unapparent , unnoticeable , unseeable , unseen, vague