Definition of inertial in English:

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Pronunciation: /iˈnərSHəl/


chiefly Physics
1Relating to or arising from inertia.
Example sentences
  • Another way of understanding the situation is to remember the equivalence Einstein explained between gravitational and inertial forces.
  • The interesting thing is that, physically, no difference has been found between gravitational and inertial mass.
  • Einstein warmed to the idea that the gravitational field of the rest of the Universe might explain centrifugal and other inertial forces resulting from acceleration.
1.1(Of navigation or guidance) depending on internal instruments that measure a craft’s acceleration and compare the calculated position with stored data.
Example sentences
  • Inside is a guidance control unit with inertial navigation and global positioning systems.
  • A rocket's inertial guidance system measures acceleration along three principal directions.
  • The missile has new GPS / INS (global positioning / inertial navigation) guidance and kinetic warhead.
1.2(Of a frame of reference) in which bodies continue at rest or in uniform straight motion unless acted on by a force.
Example sentences
  • Simple laws apply to constant motion in a straight line (an inertial frame of reference).
  • A reference frame in which star motion is ignored and the stars are assumed to be at rest is approximately an inertial reference frame and is often adequate for many purposes.
  • The rest-mass of a body is the inertial mass of that body when it is at rest relative to an inertial frame.

Words that rhyme with inertial

commercial, controversial, Herschel, infomercial

For editors and proofreaders

Syllabification: in·er·tial

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