The American Heritage® Dictionary of the English Language, 4th Edition
n. A unit of length equal to one hundred-millionth (10-8) of a centimeter, used especially to specify radiation wavelengths. Also called angstrom unit. See Table at measurement.
n. A very small unit of length, 10-10 m, approximately the size of an atom, used especially to measure the wavelength of electromagnetic radiation or distances between atoms. Symbol Å
Word Usage
"TEAM 0.5 is capable of producing images with a resolution of one-half angstrom, which is less than the diameter of a single hydrogen atom."