M: What would you call it if it’s not cannibalism, but someone eats an alien species that is certainly self aware and intelligent?
G: TLDR: The most fitting term is likely "xenophagy" (eating the other), or more specifically, "sapientophagy"—the consumption of a sapient (self-aware, intelligent) being that isn’t the same species.
Xenophagy: Greek xenos (stranger/foreigner) + phagein (to eat). General term for eating alien or foreign beings. Neutral on intelligence.
Sapientophagy: From sapient (self-aware/intelligent) + phagy (eating). This precisely implies eating a sapient creature, regardless of species. Rare but clear.
Sentientophagy: Similar to above, but “sentience” is weaker than “sapience.” Less precise if the point is high intelligence.
Exocannibalism (misleading): Normally used for eating other humans outside one’s group/tribe. Not quite right for aliens.
Anthropophagy: Specifically human-eating-human. Not applicable unless the alien is considered human-equivalent in kind.
Murder with consumption: If the alien is sapient and has rights, then this could legally/ethically fall under a form of homicide + corpse desecration.
If you're working in fiction or philosophical contexts, you could coin a term like:
But sapientophagy is probably the cleanest technical term if you want precision without inventing jargon.