In what way is language arbitrary?

A language is arbitrary in the sense that the lexical items and syntactical units used have no real correlation between them and the meaning of them. An example would be that the world Apple only means apple because people gave it that meaning, but there is nothing specific about the word itself that refers to the apple as a fruit and an idea.

Fighting to the end
Ending it all is not an option
Now you must follow your dreams
Can you show how strong you really are?
Enveloping yourself in sounds of a crowd
Seeing the yourself as the star you truly are...