A nanometre (in American English nanometer) is 10-9 metres. Its abbreviation is nm. It is an SI measure of length, commonly used in measuring the wavelengths of ultraviolet radiation and gamma rays; amongst other things. For a list of objects several nanometres large, see 1 E-9 m.

1 nm = 1000 picometre.
1000 nm = 1 micrometre aka 1 micron.

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