The throw-taking hitbox is one kind of hitbox; it determines where one can be grabbed by an opponent’s throw hitbox.
At first glance, throw-taking hitboxes can seem the same as damage hitboxes; however, while they often coincide, the damage hitbox concerns strikes, whereas the throw-taking hitbox only concerns throws, and the latter can (and often does) get treated separately from the former.
For situations where it is absolutely essential not to fall into a throw, attack avoidance and emergency evasion is recommended.