Sometimes a relative pronoun doesn't refer to a specific person or thing — it refers to an idea, a situation, or a whole clause. For this job, Spanish has two neuter relative forms: lo que and lo cual. The little word lo is a neuter article that signals "this isn't a masculine or feminine noun; it's an abstract concept."
Lo que — "what" / "that which"
Lo que is by far the more common of the two. It means what in the sense of "that which" — it's the same word you'd use in sentences like "I don't know what he wants" or "what you said made me think."
No sé lo que quiere.
I don't know what he wants.
Lo que dijiste me hizo pensar.
What you said made me think.
Dime lo que piensas.
Tell me what you think.
Lo que más me gusta es el chocolate.
What I like the most is chocolate.
The key test: can you substitute the phrase "that which" in English and still make sense? If yes, use lo que in Spanish.
Don't confuse with qué
The question word qué (with an accent) also translates as what, but in questions and indirect questions. Lo que is used in statements.
¿Qué quieres?
What do you want? (direct question)
No sé qué quieres.
I don't know what you want. (indirect question)
Lo que quieres no existe.
What you want doesn't exist. (statement)
The tricky one is the middle sentence: no sé qué quieres versus no sé lo que quieres. Both are correct and mean roughly the same thing. No sé qué quieres feels a little more like a direct question embedded in the sentence; no sé lo que quieres feels slightly more like a general statement. In speech, the two are interchangeable.
lo que. If it's a genuine question, use qué.Lo cual — "which" referring to a whole clause
Lo cual means which, but not which as in "which book?" — that's qué libro or cuál libro. Lo cual means which in the sense of referring back to a whole situation or idea, not just a single noun.
Llegó tarde, lo cual me molestó.
He arrived late, which bothered me.
Here lo cual doesn't refer to "him" or "late" specifically — it refers to the whole fact that he arrived late. The English which works the same way.
Decidió estudiar medicina, lo cual nos sorprendió a todos.
He decided to study medicine, which surprised us all.
No quisieron venir, lo cual me pareció raro.
They didn't want to come, which seemed strange to me.
Lo cual vs lo que in this use
When referring to a whole clause, you can use either lo cual or lo que. There's a subtle difference: lo cual is slightly more formal and is preferred in writing, while lo que is more conversational.
Llegó tarde, lo que me molestó.
He arrived late, which bothered me.
Both versions are correct, and Spanish speakers switch between them freely. You can't go wrong with either choice.
After prepositions
Both lo que and lo cual can follow a preposition. When they do, the meaning is still "what" / "which," but applied to an abstract concept.
Hablamos de lo que pasó en la reunión.
We talked about what happened in the meeting.
No estoy de acuerdo con lo que dijiste.
I don't agree with what you said.
Todo lo que — "everything that"
A very common expression in Spanish is todo lo que, meaning "everything that" or "all that." It's the phrase you use to describe the complete set of things involved in something.
Todo lo que dijo es verdad.
Everything he said is true.
Haré todo lo que pueda.
I'll do everything I can.
Te daré todo lo que tengo.
I'll give you everything I have.
Notice the structure: todo + lo que + verb. This is such a fixed formula that you should memorize it as a chunk.
Takeaway
The neuter lo que and lo cual fill a gap that English handles with what and which. Spanish keeps these forms separate from the noun-based relatives (que, el que, quien) because they refer to abstract ideas rather than concrete nouns. Once you recognize them, you'll start noticing them everywhere — they're hugely common in natural speech and writing.
Related Topics
- Relative Pronoun: QueB1 — Que is the most common relative pronoun — 'that', 'which', 'who'
- El Que and El CualB2 — Longer relative forms used for emphasis or after prepositions
- Cuyo (Whose)B2 — Cuyo means 'whose' and agrees with the thing possessed, not the possessor