Unit Definition (attometer) An Attometer (or attometre) is equal to one quintillionth of a meter, or sometimes denoted as 10e-18 meters. The origin of the prefix is atten, the word for 18 in Danish and Norwegian.
Unit Definition (nanometer) Equal to 0.000000001 meters (formerly millimicron), or 0.03937 microinch.
Length/Distance 
