/dɛns/ , /dɛns/
Having relatively high density.
Compact; crowded together.
Thick; difficult to penetrate.
Opaque; allowing little light to pass through.
Obscure, or difficult to understand.
Being a subset of a topological space that approximates the space well. See Wikipedia article on dense sets for mathematical definition.
(of a person) Slow to comprehend; of low intelligence.