Stonefly

Part of speech: noun

Definitions

1. An aquatic insect with flattened body and two tail filaments whose nymphs live under stones in clean, fast-flowing streams
2. A slender winged insect belonging to the order Plecoptera, whose larvae develop underwater and are sensitive to pollution
3. Any member of the order Plecoptera, a group of insects whose aquatic young cling to rocks in cold, oxygen-rich water

Etymology: Stoneflies get their name from the stony, gritty habitats their nymphs favour: they live under rocks and between pebbles on the beds of clean, fast-flowing streams. The adult insect is a weak, short-lived flier that rests on rocks and vegetation near the water, so the "fly" half is accurate even if the insect is a poor one. The word is a plain compound of "stone" and "fly", with no metaphor or borrowing involved. Its parts are both native English words of ancient Germanic descent, so the name needed no Latin or Greek to describe an insect that lives among stones and is a member of the winged insect group.