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Meaning & use

picometer

noun·Advancedtechnical

Last updated

UK/ˈpiːkəʊˌmiːtə/
US/ˈpiːkoʊˌmiːtər/

Meaning

  1. nouncountablephysicschemistry

    A unit of length equal to one trillionth of a meter, used for measuring atoms and chemical bonds.

    Grammar: Written pm after a number: 120 pm. British spelling is picometre.

    Patterns

    • measured in picometers
    • an atom of radius 100 picometers

    A hydrogen atom has a radius of about fifty-three picometers.

    Chemists measure bond lengths in picometers rather than meters.

    The X-ray wavelength was only a few picometers long.

Word forms

pluralpicometers

Common combinations

measured in picometers
Atomic radii are measured in picometers.
a few picometers
The bond differs by only a few picometers.
hundreds of picometers
Most atoms are hundreds of picometers across.
picometer scale
At the picometer scale, individual atoms can be resolved.
picometer precision
The microscope works with picometer precision.

Synonyms and how they differ

pm
Pm is the written symbol of the same unit, used with numbers in scientific text.
angstrom
An angstrom is one hundred picometers, so it is a larger, older unit often used for atoms.
nanometer
A nanometer is one thousand picometers, used for slightly bigger structures like viruses.

Word family

pico- prefix
meaning one trillionth
meter noun
the basic unit of length
nanometer noun
one billionth of a meter
picosecond noun
one trillionth of a second

Commonly confused: picometer or picometre? picometer or nanometer?

picometer vs picometre

Picometre is simply the British spelling of the same word.

picometer vs nanometer

A nanometer is a thousand times larger than a picometer.

Practice

How does a picometer compare with a nanometer?

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