What does alulae mean?
"Alulae" is the plural of "alula," a specialized anatomical term for the small cluster of feathers found on the leading edge of a bird's wing at the wrist joint — often informally called the "bastard wing." During slow flight and landing, birds can lift these feathers to create a slot that smooths turbulent airflow over the wing, preventing stalling much as the slats on an aircraft wing do. The term also has an entomological sense, describing a small lobe near the base of some insects' wings. Derived from the Latin "alula," a diminutive of "ala" meaning "wing," the word belongs firmly to scientific vocabulary and appears chiefly in ornithology, entomology, and aerodynamics literature. Its enduring interest lies in the way it connects avian anatomy to human engineering: the alulae are a natural solution to a flight problem that aircraft designers only solved in the twentieth century.
nounThe plural of "alula": the small group of feathers, or the corresponding feathered lobe, on the leading edge of a bird's wing at the "wrist," sometimes called the bastard wing; in entomology, a small lobe near the base of an insect's wing.
- In ornithology: the small group of feathers on the leading edge of a bird's wing at the wrist joint, which helps control airflow during slow flight and landing (plural of alula).
- In entomology: a small lobe or scale-like structure near the base of certain insects' wings.
"The falcon flared its alulae to stall gracefully before landing on the cliff ledge."
"As the heron came in to land, it raised its alulae, creating a slot along the wing's leading edge that kept it stable at low speed."
"Under the microscope, the entomologist noted the small alulae at the base of the moth's hindwings."
"Alulae" is itself the standard plural of "alula"; the Latin plural is retained rather than an English-style plural being formed.
"Both of the eagle's alulae were clearly visible as it banked into the wind."
Birds were flying with built-in wing slats millions of years before engineers invented them — and the alulae are those tiny feathers doing the job.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of alulae
"Alulae" comes from Latin, where "alula" is a diminutive of "ala," meaning "wing" or "armpit" — literally a "little wing." The term was adopted into modern scientific Latin and passed into English usage through ornithological and anatomical writing, retaining its original Latin plural form. Related words sharing the same root include "ala," "alate" (winged, as of insects), and "alar" (relating to wings).
Related word forms
How alulae is actually used
"Alulae" is a technical term used mainly in ornithology, entomology, and comparative anatomy; it rarely appears outside scientific writing. It is always plural — the singular form is "alula." Like many anatomical terms borrowed from Latin, it retains a Latinate plural rather than taking an English-style plural.
Easily confused with alulae
"Alula" is the singular form referring to one such feathered structure on a single wing, while "alulae" is its plural, referring to the structures collectively or on both wings.