Density

google

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early 17th century: from French densité or Latin densitas, from densus ‘dense’.

wiktionary

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Borrowed from Middle French densité or Latin densitas.

Morphologically dense +‎ -ity

etymonline

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density (n.)

c. 1600, "quality of being very close or compact," from French densité (16c.), from Old French dempsité (13c.), from Latin densitas "thickness," from densus "thick, dense" (see dense). In physics, "the mass of matter per unit of bulk," 1660s.