ang.strom 'a<nj>-str<e>m also '<o.><nj>- n (1897) [Anders J. <A^o>ngstr<o:>m]
:a unit of length equal to one ten-billionth of a meters -- used esp.
for wavelengths of light.
(= (Quantity.Dimension Angstrom) Length-Dimension) (= Angstrom (/ Meter (Expt 10 10)))