Define nadir. nadir synonyms, nadir pronunciation, nadir translation, English dictionary definition of nadir. n. 1. Astronomy A point on the celestial sphere directly below the observer, diametrically opposite the zenith. 2. The lowest point: the nadir of their...
Annular tear â definition and causes. By Michael Perry, M.D. An annular tear is one of the most common degenerative spine conditions that develop with the natural aging process of the spine. In fact, many people over the age of 50 have an annular tear and never know it.
Medical Definition of oblique fissure. : either of two fissures of the lungs of which the one on the left side of the body separates the superior lobe of the left lung from the inferior lobe and the one on the right separates the superior and middle lobes of the right lung from the inferior lobe.