From Middle High German roum. The expected modern form would be Raum, which has been ousted by a dialectal form due to the identicalness with Raum (“room”) (from Middle High German rūm). Dialects that have developed Middle High German -ou- into -ā- are found in south-eastern and central-western Germany. Cognate with Dutch room.
- cream (milkfat)
In German standard German, Rahm is used mainly in compounds (such as Rahmsoße, Sauerrahm etc.); otherwise Sahne is much more common. This is not necessarily true of colloquial varieties nor of standard German in Austria and Switzerland.
- Creme (“cream” in the sense of “frosting”)
- Rahm in Duden online