epäpuhdas

Epäpuhdas is a Finnish adjective meaning not pure or not clean, used to describe substances, materials, or environments that contain impurities or contaminants. It is formed with the negative prefix epä- attached to puhdas (clean, pure). The term can apply to physical cleanliness as well as to non-physical notions of purity.

In everyday language epäpuhdas can refer to dirtiness or uncleanliness, such as epäpuhdas vesi (impure water) or epäpuhdas lattia (dirty floor). In technical, industrial, or regulatory contexts it signals that a substance or process does not meet purity standards, for example epäpuhdas yhdiste (impure compound) or epäpuhdas tuotemateriaali (contaminated material). The opposite adjective is puhdas (pure, clean).

The noun form epäpuhtaus (impurity, contamination) is closely related, used to describe the condition or amount of impurity. Epäpuhtaus can appear in scientific, environmental, or quality-control discussions, sometimes alongside terms like saaste (pollutant) or kontaminaatio (contamination).

Figurative usage is possible, with epäpuhdas used to describe motives, policies, or arguments as not purely intended or morally clean, though this is more context-dependent and stylistically varied.

See also: puhdas, epäpuhtaus, saaste, kontaminaatio.