- annelid (n.)
- "segmented worm," 1834, from French annélide, source of the phylum name Annelida, coined in Modern Latin 1801 by French naturalist J.B.P. Lamarck (1744-1829), from annelés "ringed ones" (from Latin anulus "little ring," a diminutive of anus; see anus) + Greek eidos "form, shape" (see -oid).
- annulus (n.)
- 1560s, medical, from misspelling of Latin anulus "little ring, finger ring," a diminutive of anus (see anus).