subatomic (adj.)

• atomic
• atomistic
• corpuscular
• cyclic
• diatomic
• embryonic
• evanescent
• germinal
• granular
• heterocyclic
• homocyclic
• impalpable
• imperceptible
• imponderable
• inappreciable
• indiscernible
• infinitesimal
• intangible
• invisible
• isocyclic
• isotopic
• microcosmic
• microscopic
• molecular
• monatomic
• tenuous
• thin
• ultramicroscopic
• unseeable