The superlative form of dense; the most closely packed, thick, or tightly compressed.
From dense + -est (superlative suffix). English marks the highest degree of an adjective using -est (for short adjectives) or 'most' (for longer ones); 'densest' follows the -est pattern.
Lead is one of the densest metals you can easily hold, but neutron stars are the densest objects in the universe—a teaspoon of neutron star material would weigh more than all the cars on Earth combined, which makes your brain hurt.
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