[ek-soh-sfeer] /ˈɛk soʊˌsfɪər/
the highest region of the atmosphere, where the air density is so low that a fast-moving air molecule is more than 50 percent likely to escape from the atmosphere instead of hitting other molecules.
the outermost layer of the earth’s atmosphere. It extends from about 400 km above the earth’s surface
The outermost region of the Earth’s atmosphere, beginning at an altitude of approximately 550 km to 700 km (341 to 434 mi) and merging with the interplanetary medium at around 10,000 km (6,200 mi). The exosphere consists chiefly of ionized hydrogen, which creates the geocorona by reflecting far-ultraviolet light from the Sun. On the remote edges of the exosphere, hydrogen atoms are so sparse that each cubic centimeter might contain only one atom; furthermore, the pressure and gravity are weak enough that atoms in the exosphere can escape entirely and drift into space. Artificial satellites generally orbit in this region. See also mesosphere, stratosphere, thermosphere, troposphere., See illustration at atmosphere.
[ek-suh-spawr, -spohr] /ˈɛk səˌspɔr, -ˌspoʊr/ noun, Botany, Mycology. 1. the outer coat of a . /ˈɛksəʊˌspɔː/ noun 1. the outer layer of the spores of some algae and fungi
[ek-soh-spawr-ee-uh m, -spohr-] /ˌɛk soʊˈspɔr i əm, -ˈspoʊr-/ noun, plural exosporia [ek-soh-spawr-ee-uh, -spohr-] /ˌɛk soʊˈspɔr i ə, -ˈspoʊr-/ (Show IPA) 1. .
[ek-so-stoh-sis, -suh-] /ˌɛk sɒˈstoʊ sɪs, -sə-/ noun, plural exostoses [ek-so-stoh-seez, -suh-] /ˌɛk sɒˈstoʊ siz, -sə-/ (Show IPA). Pathology. 1. the abnormal formation of a bony growth on a bone or tooth. /ˌɛksɒˈstəʊsɪs/ noun (pl) -ses (-siːz) 1. an abnormal bony outgrowth from the surface of a bone exostosis ex·os·to·sis (ěk’sŏ-stō’sĭs) n. pl. -ses (-sēz) A […]
- Exostosis cartilaginea
exostosis cartilaginea exostosis car·ti·la·gin·e·a (kär’tl-ə-jĭn’ē-ə) n. An ossified chondroma arising from the epiphysis or joint surface of a bone.