aritmeettisessa

aritmeettinen is a Finnish adjective derived from the noun aritmeetti, meaning "arithmetic". The word is used to describe anything related to basic arithmetic operations such as addition, subtraction, multiplication, or division. In everyday language it often appears in contexts like aritmeettiset kielioppioppaat, meaning "arithmetical grammar guides," or aritmeettinen ongelma, meaning "arithmetical problem".

The form aritmeettisessa represents the inessive case of the adjective, typically used with nouns to indicate that something exists within the realm of arithmetic: for example, "luvut välittävät aritmeettisessa suhteessa toisiinsa" translates to "numbers are related in an arithmetical relationship." The inessive case is common in Finnish for expressing location or state, and here it marks that the action or property belongs inside the sphere of arithmetic, not outside it. This form is grammatically consistent with other inessive uses such as "talossa" (in the house) or "koirassa" (in the dog). The suffix -ssa adds spatial or conceptual connotation, thereby enriching the descriptive precision of the language.