vis inertiae

From Latin.

vis inertiae (uncountable)

1. The natural resistance of matter to any force acting on it.
   • 1791, James Boswell, Life of Johnson, Oxford 2008, p. 850:

     I would have something that can dissipate the vis inertiæ and give elasticity to the muscles.

2. (by extension) Inactivity; apathy.
   • 1751, [Tobias] Smollett, chapter 1, in The Adventures of Peregrine Pickle […], volume I, London: Harrison and Co., […], published 1781, OCLC 316121541:

     [H]er admonitions, tho' they were powerful enough to convince, would have been insufficient to overcome the languor and vis inertiæ of her brother, had she not reinforced her arguments, by calling in question the credit of two or three merchants, with whom he was embarked in trade.

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