Kertautuu

Kertautuu is a Finnish verb that describes something becoming multiplied, compounded, or occurring repeatedly in several instances. It is used to express that a quantity or effect increases in steps or accumulates over time, rather than rising by a single, simple amount. The term appears in everyday language as well as in academic and professional contexts, including economics, medicine, statistics, and demography.

The form kertautuu is the third-person singular present tense, passive voice, of kertautua. Related forms include kertautui (past), kertautunut (past participle), and kertautuminen (the process of becoming multiple, multiplication, recurrence). The noun kertautuminen is used for “multiplication” or “recurrence” and the verb often goes with objects such as kustannukset kertautuvat (costs multiply) or vaikutukset kertautuvat (effects accumulate).

Usage notes: The word tends to be found in formal or technical writing more than in casual speech. It conveys a sense of multiplicative growth or repetition rather than a simple increase. In mathematical or epidemiological contexts, kertautuminen can describe exponential-like growth or the repetition of events across studies or time periods.

Etymology and related terms: Kertautuu derives from kerta, meaning “time” or “occasion,” combined with a verbal suffix that signals a process. It is related to terms such as moninkertaistua (to become a multiple of itself) and kertaus (repetition).