tiheentyä
Tiheentyä is a Finnish intransitive verb that describes a change of state toward greater density or thickness. It can refer to a liquid or semi-liquid that becomes thicker, as well as to phenomena that grow more crowded or compact, such as fog, smoke, or a gathering of people. The term is commonly used in meteorology, cooking, and everyday description of changing textures or densities.
Etymologically, tiheentyä is formed from the adjective tiheä (dense, thick) with the suffix -nty- that marks
In practical use, tiheentyä describes natural and perceptible thickening. For example, sumu tiheentyy aamulla (the fog