Empty Words

A young girl came into the shop. I must say that it is a rather odd shop. You will never find any food or funiture in here but only a good idea, a fairy tale ending or a suitable rhyme.
She lingered for a while before asking hesitantly.
"Excuse me, sir... Do you have any empty words?" - Her voice trembled, as though she was not supposed to be in the shop.
"Er...what kind of words do you mean, my dear? "
"Well... An empty word is a that word which already exists but still doesn't have any meaning attached to it."