Pronunciation: [vˈɜːtɪbɹˌiːz] (IPA) 
The correct spelling of the word is "vertebrae", with the pronunciation /vɜrtɪbreɪ/. The confusion with the spelling of "vertebraes" may stem from a misunderstanding of the plural form of the word. "Vertebra" is a singular noun, and its plural form is "vertebrae", which is also pronounced with a long "e" sound at the end. The addition of an "s" at the end of "vertebrae" is unnecessary because the word is already pluralized.
Vertebrae, plural of vertebra, refers to the segmental bones that constitute the vertebral column or spine of a vertebrate organism. These bony structures serve as the central axis and protective structure for the spinal cord, providing support and flexibility to the body.
A vertebra typically consists of a round or irregularly shaped central body, called the centrum, and various bony processes extending from it. These processes include neural arches, which create a channel to encase the spinal cord, and transverse and spinous processes, which aid in muscle attachment.
The human vertebral column is composed of 33 vertebrae, including 7 cervical vertebrae in the neck, 12 thoracic vertebrae in the chest area, 5 lumbar vertebrae in the lower back, 5 fused sacral vertebrae forming the sacrum, and 4 fused coccygeal vertebrae forming the tailbone. The individual vertebrae are separated by intervertebral discs, which act as shock absorbers and allow movement between the vertebral bodies.
In addition to humans, other vertebrate animals such as mammals, reptiles, birds, and fish possess varying numbers and shapes of vertebrae. The structure of vertebrae can differ between species, reflecting different evolutionary adaptations for different modes of locomotion and body support.
The study of vertebrate anatomy and the classification of vertebrate animals often involve a detailed examination of their vertebrae, as they provide important information regarding an organism's movement, function, and evolutionary history.
