| atlantoaxial joint | <anatomy> Compound joint between first and second cervical vertebrae, the atlas and axis bones. (20 Jun 2000) |
|---|---|
| atlantoaxial subluxation | <radiology> Arthritic, rheumatoid arthritis, JRA, psoriatic arthritis, ankylosing spondylitis (late feature in 2%), lupus (systemic lupus erythematosus), congenital, Down syndrome (in 20%), Morquio disease, atlanto-occipital fusion, congenital absence/hypoplasia of dens (2/3 have history of trauma), infectious, retropharyngeal abscess, traumatic (12 Dec 1998) |
| atlantodidymus | <embryology, obstetrics> Conjoined twins with two heads on one neck and a single body. Synonym: atlodidymus. Origin: atlanto-+ G. Didymos, twin (05 Mar 2000) |
| atlantoepistrophic | <anatomy> Pertaining to the atlas and the axis; denoting the joint between the first two cervical vertebrae. Synonym: atlantoepistrophic, atloaxoid. (05 Mar 2000) |
| atlas | 1. One who sustains a great burden. 2. <anatomy> The first vertebra of the neck, articulating immediately with the skull, thus sustaining the globe of the head, whence the name. 3. A collection of maps in a volume. Supposed to be so called from a picture of Atlas supporting the world, prefixed to some collections. This name is said to have been first used by Mercator, the celebrated geographer, in the 16th century. 4. <chemistry> Atlas powder, a nitroglycerin blasting compound of pasty consistency and great explosive power. Origin: L. Atlas, -antis, Gr, one of the older family of gods, who bears up the pillars of heaven; also Mt. Atlas, in W. Africa, regarded as the pillar of heaven. It is from the root of to bear. See Tolerate. Source: Websters Dictionary (01 Mar 1998) |
| atlas fracture | <radiology> Incidence: 4% of cervical spine injuries, site: posterior arch, anterior arch, massa lateralis, Jefferson fracture associated with: fractures of C7 (25%), fractures of C2 pedicle (15%), extraspinal fractures (58%) (12 Dec 1998) |
| atlo-occipital | <anatomy> Relating to the atlas and the occipital bone. Synonym: atlo-occipital. (05 Mar 2000) |
| atloaxoid | <anatomy> Pertaining to the atlas and the axis; denoting the joint between the first two cervical vertebrae. Synonym: atlantoepistrophic, atloaxoid. (05 Mar 2000) |
| atlodidymus | <embryology, obstetrics> Conjoined twins with two heads on one neck and a single body. Synonym: atlodidymus. Origin: atlanto-+ G. Didymos, twin (05 Mar 2000) |
| atloid | <anatomy> Relating to the atlas. Anterior; cephalic. Source: Websters Dictionary (01 Mar 1998) |
| atm | Symbol for standard atmosphere. (05 Mar 2000) |
| atmo | 1. <prefix> Prefix denoting steam or vapor; or derived by action of steam or vapor. 2. <physics> The standard atmospheric pressure used in certain physical measurements calculations; conventionally, that pressure under which the barometer stands at 760 millimetres, at a temperature of 0 deg Centigrade, at the level of the sea, and in the latitude of Paris. Origin: Contr. Fr. Atmosphere, G. Atmos, steam, vapor Source: Websters Dictionary (20 Jun 2000) |
| atmological | Of or pertaining to atmology. Source: Websters Dictionary (01 Mar 1998) |
| atmologist | <specialist> One who is versed in atmology. Source: Websters Dictionary (01 Mar 1998) |
| atmology | <physics, study> That branch of science which treats of the laws and phenomena of aqueous vapor. Origin: Gr. Vapor. (04 Mar 1998) |