Pohjasanan

Pohjasanan is a term used in Finnish linguistics to refer to a word’s base form, often equivalent to what is commonly called a lemma. It is the form from which inflected and derived forms are built, and it typically carries the core lexical meaning of the word. The form pohjasanan is the genitive of pohjasana, used when discussing the concept in prose.

In many cases the pohjasana coincides with the dictionary form of a word, but the exact relationship can vary across languages and analyses. For Finnish, the pohjasana serves as the reference form for lemmatization and morphological analysis: different inflected forms such as talossa (inessive) or talon (genitive) are derived from the pohjasana talo. For verbs, a common pohjasana is the infinitive form, from which finite and participial forms are generated, such as sanoa leading to sanon, sanoi, and sanomassa.

The concept is used in lexicography, language teaching, and computational linguistics. Identifying the pohjasana enables dictionaries to group related word forms under a single entry and supports natural language processing tasks like stemming and lemma-based search.

Origin and terminology: pohja means base or foundation, and sana means word. The term highlights a foundational form that anchors morphological variation rather than the full set of inflected forms.

See also: lemma, stem, root word, inflection, lemmatization, Finnish morphology.