OBJECTIVE 



883 



OBTUXDITV 



wn, thought of, or signified. 2. A purpose, aim, 

 or end. O. -blindness. See Apraxia. 

 Jbjective [pb-jek' -tiv) [objicere, to throw against]. In 

 medicine, a qualification applied to the symptoms ob- 

 served by the physician, in distinction from those 

 felt only by the patient. In psychology, pertaining to 

 all things lying external to one's self, in contradistinc- 

 tion to subjective, pertaining to the essential ego, or 

 observer. The lens of a compound microscope 

 nearest the object viewed. O., Achromatic, the ob- 

 jective of a microscope in which the lenses, formed 

 of crown-glass and flint-glass, tend to eliminate the 

 color, or chromatic aberration. O., Adjustable, in 

 microscopy, one in which the distance between 

 the systems of lenses may be changed at the will of 

 the observer. O., Aplanatic [o priv. ; Tr/.ai^roc , 

 . wandering], in the microscope, an objective in which 

 both chromatic and spheric aberration are avoided. 

 O., Apochromatic, one in which the lenses, made of 

 a peculiar kind of glass, admit of the combination 

 of the rays from three spectral colors at one focus, 

 instead of two colors, as in the ordinary achromatic 

 objective. O., Dry, in the microscope, one in which 

 the medium between the objective and the cover- 

 glass consists of air. O., Endomersion, a form of 

 objective, devised by Zeuger, in which the chromatic 

 aberration is removed by the employment of a liquid 

 (as a mixture of ethereal and fatty oils) placed be- 

 tween the separate lenses. O., Homogeneous Im- 

 mersion, one between which and the cover-glass a 

 fluid of the same refractive index as glass is placed, 

 i Cedar-oil is such a fluid. O., Immersion, one in 

 which some fluid is placed between the front of the 

 objective and the cover-glass. O., Microscopic, the 

 systems of lenses at the lower end of the tube near 

 theobject, giving an enlarged and inverted real image. 

 These objectives are of two classes. Dry and Immer- 

 sion. O., Non-achromatic, an objective which pro- 

 duces an image with a colored border. It also permits 

 spheric aberration. O., Non-adjustable, an objec- 

 tive in which the relative positions of the lenses or 

 lens-systems are fixed. O., Oil-immersion, an ob- 



ective between which and the object a drop of oil 

 is placed. Cedar-oil is most commonly employed. 

 O., Unadjustable. See O., Non-adjustable. O., 

 Water-immersion, an objective between which and 



he cover-glass water is placed as a medium. 



'lanceolate [ob-lan'-se-o-lat) [ob, reversed; lanceola, 

 tie lance]. In biology, lanceolate, with the apex 

 vard. 



1'ligate (ob'-lig-at) [obligalus, obligare, to oblige], 

 n biology, necessary, essential, constrained, bound. 

 3. Aerobic, See Aerobic. O. Anaerobic. See 

 Aerobic. O. Parasite, an organism which is con- 

 trained to a parasitic life for the attainment of its 

 levelopment. 

 i ligatory (ob-lig' -at-or-e) [obligare, to bind]. Com- 



'elling; binding. O. Aerobes. See Aerobic. 

 < lique {ob-lek' or ob-lik') [okliquus, oblique, slant- 

 ig]- Not direct; aslant: slanting. In botany, un- 

 1 sided. In anatomy, an oblique muscle, as the 

 xternal or internal oblique of the abdomen, or the 

 ' uperior or inferior oblique of the eye. 

 Uiquity {ob-lik'-nnt-e\ [obliquitas, obliqueness]. The 

 ate of being oblique. O., Naegele's, in ob-tetrics 

 iteral inclination of the fetal head, in conse- 

 quence of which the sagittal suture is directed more 

 >3teriorlv. O., Rcederer's, in obstetrics, the ex- 

 mely flexed position of the fetal head on the body. 

 >-, Solayres's, in obstetrics, the entrance of the 

 ■tal head into the pelvic inlet in an oblique diame- 



Obliquus {ob-li'-kwus) [L., slanting]. Slanting; ob- 

 lique. A term applied to various muscles. O. Mus- 

 cle. See Muscles, Table of. O. Reflex. See Re- 

 flexes, Table of. 



Obliterate {ob-lit'-er-af) [obliterare, to erase]. To 

 wipe out. In biology, indistinct ; applied to marks, 

 spots, punctures, and striae, in animals. 



Obliteration {ob-lit-er-a' '-shun) [obliteratio ; obliterare, 

 to efface]. Extinction of a part; closure, as of the 

 lumen of a passage. 



Oblivion {ob-liv' -e-on) [oblivio, lethargy]. Forgetful - 

 ness ; lethargy. 



Oblongata (ob-leng-gah'-tati) [L.]. The medulla ob- 

 longata. 



Oblongatal (ob-long-ga'-tal) [oblongata , the medulla]. 

 Pertaining to the oblongata. 



Obmutescence (ob-mu-tes'-ens) [obmutescere, to become 

 dumb]. Aphonia; loss of voice. 



Obnubilation (ob-nu-bil-a / -shun) [obnubilare, to be- 

 cloud]. A beclouded state of the mind or spirit. 



Obovate {ob-o'-vdt) [ob, reversed ; ovatus, egg-shaped]. 

 In biology, inversely ovate. 



Obovatifolious ( ob-o-va-tif-o' -le-us ) [ ob, reversed ; 

 ovatus, egg-shaped; folium, a leaf]. In biology, 

 having inversely ovate leaves. 



Obovoid (ob-o'-void) [ob, reversed; ovum, an egg]. In 

 biology, solidly obovate. 



Observation {ob-zer-va f -shun) [observatio\. The exam- 

 ination of a thing ; a systematic study of phenomena. 



Obsession [ob-sesh'-un) [obsessire, to beset]. Beset- 

 ment. Possession as by evil spirits ; an imperative 

 idea; a dominant delusion. 



Obsolescence {ob-so-les' -ens) [obsolescere, to grow old]. 

 The state of becoming old or going out of use. Also, 

 the cessation of growth. 



Obsolete [ob' -so-let) [obsoletus, p. p. of obsolescere, to 

 wear out]. In biology, indistinct, imperfectly devel- 

 oped or rudimentary. 



Obstetric (ob-stet f -rik) [obstare, to stand before]. Per- 

 taining to the practice of obstetrics. O. Position. 

 See Postures, Table of. 



Obstetrician {ob-stet-rish'-an) [obstare, to stand before]. 

 One who practises obstetrics. 



Obstetrics (ob-stet f -riks) [obstare, to stand before]. 

 The care of women in pregnancy, childbirth and the 

 puerperal state. 



Obstetrix (ob-stef -riks) [obstare, to stand before]. A 

 midwife. 



Obstipation {ob-stip-a'-shun) [obstipatio ; obstipare, to 

 close tightly]. Constipation. 



Obstipitas (ob-stip'-it-as) [obstipus, awry, stiff-necked ; 

 stipes, a stick]. Wry-neck ; torticollis. 



Obstruction {ob-struk' -shun) [obstruclio ; obstruere, to 

 stop up]. Stoppage or blocking up of a canal or 

 opening of the body. See Imperforatinn , Occlusion. 



Obstruent {ob f -stru-enf) [obstruere, to close up]. I. 

 Obstructive ; tending to obstruct. 2. In therapeutics or 

 pathology, any remedy or agent closing the lumen or 

 orifice of vessels or ducts. 



Obstupefacient {ob-stu-pe-fa'-she-ent) [obstupefacere, 

 to stupefy]. Narcotic or stupefying. 



Obstupescentia (ob-stu-pes-en'-she-ah) [L.]. A state 

 of stupefaction, with a look as of astonishment. 



Obtected (ob-tek'-ted) [ob, over; tegere, p. p., tectum, 

 to cover]. In biology, concealed under a neighboring 

 part. 



Obtund {ob-tund') [obtundere, to dull]. To blunt or 

 dull ; to lessen, as pain. 



Obtundent {ob-tun f -dent) [obtundere, to make dull]. 

 Soothing ; quieting. In therapeutics, any remedy 

 that relieves or overcomes irritation or pain. 



Obtundity {ob-tun' -dit-e) [ob undere, to make dull]. 



