Blattförmig

Blattförmig (German for “leaf‑shaped”) describes any object whose outline or three‑dimensional form resembles a typical leaf. The term is used across several scientific and technical fields, most notably in botany, zoology, mineralogy, and engineering. In botany, leaf‑shaped structures include certain stipules, bracts, or even the lamina of a leaf that deviates from the usual simple shape, such as the deeply lobed leaves of some species of *Acer* (maple) that are described as blattförmig. In zoology, the term applies to anatomical parts that have a flattened, broad, and often serrated contour, for example the blattförmige (leaf‑shaped) wings of some insects or the leaf‑like thoracic plates of certain marine crustaceans.

In mineralogy, crystals that develop a broad, planar habit with tapered ends are termed blattförmig, as seen in mica sheets that exfoliate in leaf‑like layers. Engineers may use the adjective to characterize components such as turbine blades, aerodynamic surfaces, or heat exchangers whose profiles are intentionally designed to mimic the efficient geometry of a leaf to improve fluid flow or heat transfer.

Etymologically, the word combines *Blatt* (leaf) with the suffix *‑förmig* (shaped), a productive formation in German for describing resemblance. Synonymous terms in English include “leaf‑shaped” or “lamellar.” The concept is also related to the Latin *foliatus* and the Greek *phyllodes*, both used in scientific nomenclature to denote leaf‑like forms.