-
too small to be seen without an ultramicroscope
Words sounding like good ultramicroscopic
topic microscopic tropic philanthropic telescopic psychotropic isotopic myopic stereoscopic macroscopic gyroscopic ectopic spectroscopic misanthropic ultramicroscopic pantropic neurotropic megascopic lipotropic kaleidoscopic isotropic isentropic hyperopic hypermetropic hygroscopic gonadotropic emmetropic deuteranopic adrenocorticotropic anisotropic