Invulnerable, not possible to be pierced or wounded.
As most anything can be pierced or wounded, the term without the ga'i is practically never used.
A'a iyan gey katama'an pineddang.
That person is invulnerable if slashed.
Bang inamāhan bu magsaye hadja ubus ga'i katama'an inamāhan.
If someone is scolded and he just laughs, he is invulnerable to scolding.