The Latin words that began with “cl” changed, pretty consistently, to “ll” as Latin changed into Spanish.
Today’s example of this: the Latin word for “key” was clavis. This became the modern Spanish word for “key”, llave.
There are, however, a few interesting other descendants of clavis, and thus distant relatives of llave. They include:
- the Spanish clavo, meaning, “nail”. It’s a more educated word, coming to Spanish via Latin scholars later on, so it didn’t lose the natural cl- sound the way the traditional words did.
- English words like clef and enclave. Yes, in music you talk about the “key” and the “clef” and they come from the same word originally!