Tietosanat

Tietosanat (Finnish for "content words" or "lexical words") is a term used in Finnish linguistics to refer to a broad class of words that convey substantial semantic content and belong to open word classes. They form the core vocabulary that can describe objects, properties, actions, quantities and circumstances. Common examples include nouns (substantiivit), adjectives (adjektiivit), verbs (verbit), numerals (lukusanat) and adverbs (adverbit). These words are distinguished from function words, such as conjunctions, prepositions and determiners, which primarily serve grammatical functions and tend to form closed classes.

In Finnish pedagogy and grammar descriptions, tietosanat are analyzed for morphological behavior like inflection and word formation, and for their role in building phrases and sentences. They typically carry the core meaning of a sentence and can often be replaced with different lexemes to alter meaning.

They are the focus in many lexicographic and natural language processing tasks because they are more variable and productive. The term's usage varies by source and tradition; some authors prefer to subdivide tietosanat further into lexical categories, while others use the term as an umbrella for all content words. The concept aligns with the broader linguistic distinction between content words and function words found across languages, though exact boundaries may differ.