pumpuun
Pumpuun is not a stand-alone Finnish lemma. In most contexts it appears as either a misspelling or the illative form of the noun pumppu, which means pump. The standard illative form is pumppuun, written with a double p. Because Finnish spelling preserves the base consonants, pumppuun is the conventional way to express the meaning “into the pump” in technical and descriptive language.
In Finnish, pumppu behaves like a typical noun and takes several inflected forms. The illative singular is
Usage notes: When referring to the pump in sentences, use pumppuun to mean “into the pump” and
See also: pumppu, Finnish inflection, illative case, Finnish grammar.