Qual é o sentido de palavra "WILL" nessa frase?

Long ago, there lived an old man with his three sons in a deserted village,
Located in the vicinity of a desert. He had 17 camels, and they were the main source of his income. He used to rent out camels as a means of shipping in the desert.
One day, he passed away. He had left a WILL, leaving his assets for his three sons
After the funeral and the other obligations were over, the three sons read the WILL...

Já o primeiro WILL eu pensava que seria algo tipo "Vontade" para os filho, mas depois os filhos leram o WILL, que é impossível ler a vontade.

Agradeço desde já.