Isopoda

Part of speech: noun

Definitions

1. A diverse order of crustaceans including species like pillbugs and sand hopper, characterized by having a flattened body and typically seven pairs of legs
2. An extensive group of primarily aquatic arthropods that possess a segmented body and often exhibit direct development without metamorphosis
3. A taxonomic class of invertebrates known for their unique adaptation to terrestrial and marine environments, with some exhibiting a noticeable dorsal-ventral flattening

Etymology: Isopoda is a Modern Latin coinage, built from two Greek roots: "isos" meaning "equal" and "pous" (genitive "podos") meaning "foot." The name refers to the animals' legs, which are nearly identical in shape and size along the body, unlike the varied limbs of many other crustaceans. The group was named by the French zoologist Pierre André Latreille in the early 1800s, so the name is a scientific invention rather than an ancient one, and the ancient Greeks never encountered these creatures under this label. The name reaches well beyond the sea. Many familiar land-dwelling "woodlice," such as the pill bugs and sowbugs found under logs and stones, belong to this order, so the word covers animals that have moved onto land. Its Greek parts also make it a useful descriptive key: "equal feet" points straight at the body plan that defines the group.

Synonyms: isopods