annullär

Annullär is a Swedish adjective meaning ring-shaped or forming a ring. The term is used in scientific and technical languages to describe objects, regions, or structures that resemble a ring. It is derived from the Latin annulus “a little ring” and used in Swedish with the adjectival suffix -är.

In mathematics and geometry, annullär describes the annulus, the region between two concentric circles. Formally, it consists of all points whose distance from a fixed center lies between two positive radii. The term also appears in topology and complex analysis to refer to annular domains or regions.

In astronomy, annullär describes ring-shaped appearances, such as annular solar eclipses, which occur when the Moon covers the center of the Sun but leaves a bright ring around the edges.

In biology and botany, annullär denotes ring-like structures or arrangements, such as tissues or features that encircle another structure. In mycology and related fields, the Latin term annulus is used for the ring around a mushroom stalk, and annullär may be used descriptively to refer to such ring-shaped forms.

Etymology note: the word is rooted in Latin annulus and adopted into Swedish, where the form annullär is used to convey the ring-shaped sense across disciplines. The term should be distinguished from annullera (to cancel) and related non-descriptive uses of annull in other contexts.