Pfropfen

Etymology
From, borrowed into East Central German and thence into the standard language (early 18th century). The modern form is a secondary adaptation to the Upper German consonantism, based formally on the verb (“to engraft”, eventually from 🇨🇬), which in Low and Central German had the form, thus identical to the unrelated noun. Cognate with 🇨🇬.

Noun

 * 1)  plug; something intended to plug
 * 2)  plug; clot; something that happens to plug

Usage notes

 * The normal word for sense 1 is, which cannot be used in sense 2, however. In the latter, is more northern and eastern, while  is the more southern and western word. The written language prefers.