Definition of "suprachiasmatic"
Situated above the optic chiasm; specifically, designating a nucleus or region in the paraventricular region of the hypothalamus.
Quotations
When I tell you that the suprachiasmatic nucleus is composed of 20,000 brain cells, or neurons, you might assume it is enormous, consuming a vast amount of your cranial space, but actually it is tiny.
2017, Matthew Walker, Why We Sleep, Penguin, published 2018, page 18