Zeptosecond: one-billion-trillionth of a second, or 10 -21 second. Because nuclear movement takes place so quickly, scientists would need a pulse of light lasting just one zeptosecond to observe them.


Zettatechnology: in which zetta means 1021, referring to the typical number of distinct designed parts in a product made by the systems we envision (molecular, mature, or molecular-manufacturing-based nanotechnology). The term refers to the implemented technology and its products, rather than to intermediate steps on the pathway.