plural densities
Definition of density
1
: the quality or state of being dense
measures of traffic density the density of the cake felt that the candidate's density on the subject of equality was alarming the density of her prose
2
mathematics
: the quantity per unit of volume (see volume entry 1 sense 2), unit of area (see area sense 1), or unit of length: such as
a
chemistry
: the mass (see mass entry 2 sense 1c) of a substance per unit of volume
pure iron has a density of 7.8 grams per cubic centimeter
b
chemistry
: the distribution of a quantity (such as electricity or energy) per unit usually of space (such as length, area, or volume)
The drawback to using ethanol as a complete replacement for gasoline, however, is not only the high cost of its production from cellulose but also its lower energy density.— John R. Regalbuto
c
: the average number of individuals or units per unit of space
a population density of 500 per square mile a housing density of 10 houses per acre
3
physics
a
: the degree of opacity (see opacity sense 2) of a translucent medium
the fog's density
b
: the common logarithm of the opacity
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Time Traveler for density
The first known use of density was in 1598
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