Synonyms and related words :
atomatic, atomic, atomiferous, atomistic, corpuscular, cyclic, diatomic, dibasic, embryonic, evanescent, germinal, granular, heteroatomic, heterocyclic, hexatomic, homocyclic, impalpable, imperceptible, imponderable, inappreciable, indiscernible, infinitesimal, intangible, invisible, isobaric, isocyclic, isoteric, isotopic, microcosmic, microscopic, molecular, monatomic, pentatomic, tenuous, tetratomic, thin, triatomic, tribasic, ultramicroscopic, unseeable