This is the 2351st most frequent Spanish word.
terminado
Finished; completed.
Here, 'terminado' is used as an adjective to describe the state of the book as completed.
El libro está terminado.
The book is finished.
In this sentence, 'terminado' is used as part of the present perfect tense indicating the action of completing homework has been finished.
He terminado mi tarea.
I have finished my homework.
'Terminado' here is used in the future perfect tense, describing the state of completion of everything by a future time.