Why do I need to know la vache?
This is probably one of the most commonly used French interjections and works in just about any situation.
What does it mean?
La vache (‘la vahsh’) can literally be translated as ‘the cow’, but is actually used as an expression of surprise, admiration, or disappointment, similar to ‘damn!’ or ‘oh my god!’.
English speakers often translate it as ‘holy cow!’, which is fairly accurate, except that the French actually use la vache on regular basis.
La vache can be positive, negative, or neutral depending on the context. So, in a positive sense, one could say: La vache, je crois que tu as gagné au loto! – ‘Oh my god, I think you won the lottery!’
But in a negative sense, la vache works just as well: Ah la vache! On s’est fait écraser par le PSG à nouveau. – ‘Damn! We got crushed by PSG (Paris Saint-Germain) again.’
Of course, la vache doesn’t have to positive or negative, but can just express neutral surprise, as in, Il est déjà minuit, la vache! – It’s already midnight, wow!
As you may have noticed, la vache is also often preceded by oh or ah, as in Oh la vache! Ça m’a fait peur! – ‘Whoa, that scared me!’
La vache is informal, and best suited for informal situations, but is not offensive and can be heard from French speakers of all ages.
Supposedly, this expression dates back to the 17th century, when farmers would bring a cow into town with them to demonstrate to the villagers that the milk they were selling was fresh.
The townspeople would cry out la vache! upon sighting their source of milk, and the exclamation eventually evolved to become a general expression of surprise.
Both dis donc and oh là là are similar to la vache in that they are expressions of surprise that can be positive, negative, or neutral, depending on the context in which they are used.