e/Letter combination of uu

Information
has gloss	eng: The combination uu occurs rarely in the English language and, other than continuum, muumuu and vacuum, in words which are unfamiliar or archaic. With the exception of Muumuu (Hawaiian) and (Welt)anschauung (German), they derive from Latin roots. It is highly debatable as to whether unuunilium should count, as it was firstly renamed to Ununilium, which in turn was renamed to the current Darmstadtium.
lexicalization	eng: Letter combination of uu
instance of	(noun) two successive letters (especially two letters used to represent a single sound: `sh' in `shoe') digraph, digram