siistiä

Siistiä is a Finnish word used as both an adjective meaning clean, neat, or tidy, and as an informal interjection expressing approval. In neutral use, it describes physical cleanliness or order, but in slang it signals enthusiasm or admiration for something perceived as high quality or stylish.

The base form siisti comes from siisti, meaning clean or tidy. The exclamatory siistiä is the partitive-inflected form used in spoken language to convey pleasure or excitement, as in Siistiä! or Siisti juttu. In written Finnish, the slang sense is usually understood from context and is avoided in formal styles.

Usage varies by register. Among youths and in popular culture, siistiä can praise a performance, a result, a new item, or a situation. It can also mean “cool” or “great” in a general sense, beyond mere cleanliness. In formal writing, its slang sense is typically inappropriate or marked as informal.

Variants and related terms include the adjective siisti and the adverbial form siististi, meaning neatly. The expression is widely recognized across Finland, though its tone and frequency may differ regionally and among age groups. In contemporary discourse, siistiä often conveys a positive evaluation tied to quality, attractiveness, or successful execution, rather than a literal assessment of cleanliness.

Overall, siistiä functions as a versatile Finnish slang marker of approval, while retaining a connection to the original meaning of cleanliness and order.