1. One billionth 10^(-9); more generally, very small

Encyclopedia: Nano-

• immobility
• immobilization
• immobilize
• immobilizer
• immobilizing
• immoderate
• immoderately
• immoderateness
• immoderation
• immodest
• immodestly
• immodesty
• immolate
• immolation
• immolator
• immoral
• immorality
• immorally
• immortal
• immortalise
• immortality
• immortalize
• immortally
• immortelle
• immotile