What kind of Spanish word has no meaning?

This is a bit of a trick question! There's no Spanish word that has *absolutely* no meaning. Even nonsense words or made-up words have *some* kind of meaning, even if it's just "this is a word that doesn't exist in the Spanish language."

However, here's a way to think about the question:

* "Meaningless" in the sense of being nonsensical or meaningless in a specific context: You could argue that words like "blablabla" or "flibbertigibbet" (which are English words but not Spanish) have no meaning when used in a Spanish conversation. They would be gibberish.

* "Meaningless" in the sense of being a grammatical placeholder: Sometimes in Spanish, we use words that don't have a specific meaning, but are there for grammatical reasons. For example, the word "se" can be a reflexive pronoun, a passive marker, or used in impersonal constructions. It doesn't always have a direct meaning in the way that a noun like "gato" (cat) does.

So, it really depends on how you define "meaningless"!