täydennyttää

Täydennyttää is a Finnish verb that expresses the idea of causing something to be completed or supplemented, typically by adding missing information or material. It is a relatively rare or stylistically marked form in modern Finnish, and many speakers would use a more common expression such as täydentää or refer to täydennys when speaking of completing or supplementing content.

Etymology and form: The verb is related to the semantic field of täydennys (completion, supplementation). It is formed with the same root area as täydennys and with a productive causative suffix that in Finnish can create verbs meaning “to cause to be X” or “to cause to perform the action.” As a result, täydennyttää can be interpreted as “to cause to be completed” or “to cause to be supplemented.” Because of that derivational path, it appears in some dictionaries and older or technical texts, but is not part of everyday standard usage.

Usage and register: The term is primarily encountered in written, formal, or historical texts. In everyday language, speakers typically express the idea with more common forms such as täydennellä, täydennätä, or the straightforward täydennätä/täydentää in corresponding contexts. Because täydennyttää is not common in contemporary speech, many style guides and dictionaries treat it as a variant or archaic/technical form rather than a standard synonym.

See also: täydennys; täydennätä; täytä (related verb family for completing or filling in). References to standard Finnish usage usually point to täydennätä/täydentää for the core sense of completing or supplementing content.