ultramicrometer: Meaning and Definition of

ul•tra•mi•crom•e•ter

Pronunciation: (ul"tru-mī-krom'i-tur), [key]
— n.
  1. a micrometer calibrated to a very fine scale and capable of measuring extremely small magnitudes.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.