atomic, behind the curtain, behind the scenes, camouflaged, concealed, corpuscular, disguised, embryonic, ephemeral, evanescent, faint, fugitive, germinal, granular, hidden, ill-defined, impalpable, imponderable, inappreciable, inaudible, inconsiderable, inconspicuous, indiscernible, indistinct, indistinguishable, infinitesimal, insensible, insignificant, intangible, invisible, latent, microcosmic, microscopic, minuscule, minute, molecular, momentary, obscure, out of sight, secret, sightless, slight, subatomic, submerged, subtle, tenuous, thin, tiny, trivial, ultramicroscopic, unapparent, unappreciable, unbeheld, unbeholdable, unclear, undiscernible, undistinguishable, unnoticeable, unnoticed, unobservable, unobserved, unperceivable, unperceived, unrealized, unseeable, unseen, unviewed, unwitnessed, vague, viewless