Definition of cloaca in English:
cloaca
nounPlural cloacae kləʊˈeɪkəkloʊˈeɪkə
1Zoology
A common cavity at the end of the digestive tract for the release of both excretory and genital products in vertebrates (except most mammals) and certain invertebrates.
Example sentencesExamples
- Instead, males deposit spermatophores on the substrate and females pick up these spermatophores with their cloaca later.
- Unlike we humans, the chicken has a single sexual and excretory orifice, the cloaca.
- The bursa of Fabricius is an organ located just beside the cloaca.
- After males deposit spermatophores onto the cloaca of females, up to 150 eggs are laid on mud near water.
- Salamanders were measured from the tip of the snout to the anterior end of the cloaca.
2archaic A sewer.
Example sentencesExamples
- The cloaca maxima was the sewer system built in the sixth or seventh century BC, by one of the kings of Rome.
Derivatives
adjective
Bird penile tissue, where it exists, also develops on the ventral cloacal wall.
Example sentencesExamples
- Little is known of their reproductive biology, but the lack of both spermatheca in females, and cloacal glands in males, suggests external fertilization.
- But most birds and Sphenodon lack intromittent organs and transfer sperm by cloacal apposition.
- Birds were mist-netted or caught in seed-baited traps and sexed by examination of the cloacal protuberance.
- A current theory is that the eggs are ovulated through the cloacal pore and are expelled under pressure by muscular contractions.
Origin
Late 16th century (in the sense 'sewer'): from Latin, related to cluere 'cleanse'. The first sense dates from the mid 19th century.