NANO DEFINED

Nano: Greek for 'dwarf'

A nanometer: One-billionth of a meter. A sheet of paper is about 100,000 nanometers thick; a blond hair around 50,000 nanometers in diameter.

Nanoscience: The study of the extremely small. Involves researching behaviors and properties of materials roughly 1 to 100 nanometers in size.

Nanotechnology: The way discoveries made at the nanoscale are put to work.

Nanoparticles: Invisible to the eye and conventional microscopes, they can occur naturally or be manufactured.

Source: National Nanotechnology Initiative, Arlington, Va., and www.which.co.uk.