täysikasvuinen

Täysikasvuinen is a Finnish adjective meaning fully grown or adult. It is used of living organisms—people, animals, and plants—to denote that they have completed growth and reached a mature stage. The word is formed from täysi (full), kasvu (growth) and the suffix -inen.

In human context, täysikasvuinen describes someone who is not a child, often translated as an adult. In Finland, the legal age of adulthood is 18; however, being täysikasvuinen does not automatically imply legal rights in all circumstances, since many legal distinctions are expressed with age specifications such as 18 vuotta täyttänyt. The term is common in everyday language and in journalism when focusing on physical or social maturity rather than legal rights.

In biology and botany, täysikasvuinen is used to refer to individuals or organs that have reached the final size and stage of development; for example, täysikasvuinen eläin (adult animal) or täysikasvuinen kasvi (mature plant). It can describe sexual maturity differently across species, so a creature may be sexually mature before or after reaching full size, depending on the species.

Related terms include lapsi (child) and aikuinen (adult) as broader categories; täysikasvuinen emphasizes the completion of growth. The term is widely understood in Finnish and is used across educational, scientific, and everyday contexts.