(a.) Extremely small; minute\.

3-D atomic close constant corpuscular delicate direct embryonic evanescent even exact express faithful fine germinal granular impalpable imperceptible imponderable inappreciable indiscernible inerrable inerrant infallible infinitesimal intangible invisible mathematical microcosmic micrometrically precise molecular nice pinpoint precise refined religious religiously exact rigid rigorous scientific scientifically exact severe square stereoscopic strict subatomic subtle telescopic tenuous thin three-dimensional ultramicroscopic undeviating unerring unseeable