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Added 9 October 2026

inertia

/ɪnˈɜː.ʃə/ noun

In Latin: inertia Wiktionary

noun Definition from WordNet 3.1, Princeton University. Pronunciation from Wiktionary, via Kaikki.org. More about inertia at Wordnik → Where our words come from →

A disposition to remain inactive or inert.
he had to overcome his inertia and get back to work
(physics) the tendency of a body to maintain its state of rest or uniform motion unless acted upon by an external force.

Origin

From Latin inertia (“lack of art or skill, inactivity, indolence”), from iners (“unskilled, inactive”), from in- (“without, not”) + ars (“skill, art”). Something close to the modern physics sense was first used in New Latin by Johannes Kepler.

From Wiktionary, via Kaikki.org (CC BY-SA)

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