| Term | Definition |
| exoskeleton | hard exterior of arthropods, made of chitin |
| compound eye | eye made up of multiple lenses (ommatidium) |
| segmented body | body plan divided into 2-3 parts; allows for greater speciallization and efficiency of movement |
| jointed appendages | legs and mouth parts with joints |
| open circulatory system | circulatory system that pumps blood directly over organs rather than through vessels like arteries, veins, and capillaries |
| crustacean | group of marine arthropods with only two bodied segments, paired antennae, and an exoskeleton hardened with calcium |
| decapod | crustacean with 10 legs/feet |
| arthropoda | most successful phylum of animals, accounting for roughly 80% of all identified animal species |