llavero
keychain
llave
key
+
-ero
container or holder suffix
Llavero means keychain and can be understood as llave0 (key0) + -ero1 (container or holder1), literally a 'key holder'.
noun
- keychainA ring or holder for keysPerdí mi llavero con todas mis llaves. // I lost my keychain with all my keys.