Phyllodia

Part of speech: noun

Definitions

1. Flattened, leaf-like stalks of certain plants that take over the role of true leaves in photosynthesis
2. Expanded leaf stalks that look and function like leaves, as seen in many Australian acacia species
3. Leaf-shaped petioles, flattened and green, that perform the work of foliage in some woody plants

Etymology: "Phyllodia" is the plural of "phyllodium," a botanical term for a flattened, leaf-like petiole, the leaf stalk swollen and flattened so that it works as a leaf. Many acacias grow these in place of true leaves, which is why a wattle can look as though it has narrow green blades instead of the feathery fronds you might expect. The term comes from New Latin "phyllodium," formed from the Ancient Greek "phullōdēs," meaning "leaflike." That Greek adjective is built from "phullon," "leaf," and the suffix "-ōdēs," "resembling," so the whole word is a descriptive label for something that resembles a leaf without being one. Botanists coined the New Latin form in the modern scientific period, drawing on classical roots rather than on any ancient usage.