Insects also have brains. Some arachnids have the capacity for fairly complex cognition (e.g., the portia spider's hunting behaviors, jumping spiders communicate with eachother and in my opinion, engage in playful behavior).

The issue isn't with your terminology, but rather with what it reveals about the imprecision/inconsistency of your reasoning on these matters.

If you're going to draw a line at eating beings that can feel the harm done to them by eating, it might serve you to explore that boundary more thoroughly.