Relative pronouns after superlatives (wat)

The relative pronoun "wat"

To express ideas like "the tastiest thing" or "the most absurd thing", Dutch turns a superlative adjective into a neuter noun. You do this by placing het before the superlative and adding an -e to the end (for example, het lekkerste).

When you want to refer back to this superlative with a relative pronoun (meaning "that" or "which"), you must use wat.

This is the tastiest thing we have eaten!
Dit is het lekkerste wat we hebben gegeten!

Even though regular neuter nouns usually take dat as a relative pronoun, these nominalized superlatives always take wat. This structure is perfect for sharing strong opinions and reviews.

That is the most disgusting thing I have ever tasted.
Dat is het walgelijkste wat ik ooit heb geproefd.
The most brilliant thing the director did was change the music.
Het geniaalste wat de regisseur deed, was de muziek veranderen.

Expressing criticism

You will see this grammar pattern often when writing critical reviews of movies or restaurants using strong adjectives.

The lamest thing he said was a bad joke.
Het flauwste wat hij zei, was een slechte grap.
It was the most predictable thing the actor ever did.
Het was het voorspelbaarste wat de acteur ooit deed.

Regular nouns still use "dat"

Remember that this rule only applies to superlatives and a few other indefinite words (like alles or iets). When you refer back to a regular neuter noun (a het word), you still use dat.

It was the acting that made the movie fantastic.
Het was het acteerwerk dat de film fantastisch maakte.