x1 is x2 meter(s) [metric unit] in length (default 1) measured in direction x3 by standard x4.
See also kilto, centi, decti, dekto, femti, gigdo, gocti, gotro, gutci, litce, megdo, mikri, milti, minli, nanvi, petso, picti, terto, xatsi, xecto, xexso, zepti, zetro.