heterotrophic
An organism that depends on consuming other autotrophic organisms to survive
Humans are heterotrophic, whereas plants are autotrophic.
heterotrophic guilt
The realization that no matter which diet you follow, you're still eating organisms that were alive at one point, and we have murdered them for our own benefit.
Apparently plants can think and remember? We're killing sentient beings! Crap! Dude, I'm feeling all kinds of heterotrophic guilt right now.