Hafermilch vs. Haferdrink
In German, the terms Hafermilch and Haferdrink describe the exact same product, but they are used in different contexts due to legal regulations regarding dairy terminology.
Hafermilch
A2This word combines Hafer (oat) and Milch (milk) and is the standard term used in everyday spoken language. Although it is the most natural way to refer to the beverage colloquially, it is legally prohibited from appearing on commercial packaging within the EU.
Ich trinke meinen Kaffee am liebsten mit Hafermilch.
(I prefer drinking my coffee with oat milk.)
Hast du noch genug Hafermilch für das Müsli?
(Do you still have enough oat milk for the muesli?)
In diesem Café kostet Hafermilch keinen Aufpreis.
(In this cafe, oat milk does not cost extra.)
Haferdrink
A2This term translates to oat drink and is the official designation found on product labels in supermarkets. Because EU law protects the term Milch (milk) exclusively for animal secretions, manufacturers must print Haferdrink on the carton instead.
Auf der Verpackung steht ungesüßter Haferdrink.
(The packaging says unsweetened oat drink.)
Der Hersteller nennt sein Produkt offiziell Haferdrink.
(The manufacturer officially calls its product oat drink.)
Bitte kauf einen Liter Haferdrink im Supermarkt.
(Please buy a liter of oat drink at the supermarket.)
Summary
While the liquid is the same, use Hafermilch when speaking to friends or ordering at a coffee shop. However, expect to see Haferdrink written on the packaging when you are shopping, as the law forbids calling plant-based items milk on labels.