Invulnerable

Invulnerable or invincibility commonly refers to an ability which makes entities impossible to kill or destroy in Minecraft, except for special cases (such as through commands or void death). There are several pages which discuss this:

• Entities' [Boolean] Invulnerable tag, which makes entities invulnerable from any source of damage, except from players in Creative mode.
• Players' [Boolean] invulnerable ability in the [NBT Compound / JSON Object] abilities data, which makes players invulnerable from any source of damage except the void.
• Damage § Invulnerability timer, a short half-second invulnerability against most source of damage after sustaining another damage from any source.

• Invulnerability, an effect that prevents the hero from taking damage.