SIN 



382 



SIP 



whose root is used as a bitter 

 tonic and astringent, especially 

 in advanced stages of diarrhoea 

 and dysentery, found in Cayenne 

 and W. Indies also called S. 

 officinalis, &f-jtf>fa-AKte(L. o/ic- 

 mdlis, by authority). 



Sinapis, n., sin* dp' is (L. sindpis, 

 mustard), a genus of plants, Ord. 

 Cruciferse : Sinapis nigra, nlg'ra 

 (L. niger, black; nigra, fern.), 

 a species whose seeds furnish 

 table mustard, and which contain 

 a bland fixed oil, a peculiar bitter 

 principle, and myronic acid : S. 

 alba, alb'-d (L. albus, white), a 

 species furnishing white mustard, 

 and containing more fixed oil 

 than black mustard, is cultivated 

 as a salad : sinapin, n. , sin-dp'-m, 

 or sinapisin, n., sin-ap'-is-m, a 

 principle in ' S. alba ' analogous to 

 myronic acid, found in 'S. nigra': 

 sinigrin, n., sm'-ig-rin, a crystal - 

 lisable substance found in mus- 

 tard : sinapism, n., sin'ap~izm, 

 a poultice of which mustard is 

 the basis. 



sinciput, n., sin'si-p&t (L. sinciput, 

 the fore part of the head from 

 semi, half ; caput, the head), the 

 forepart of the head, the back 

 part being called the occiput. 



Binistral, a., sin'-is-lral (L. sinis- 

 tra, fern. , on the left hand ; sinis- 

 ter, masc.), left-handed; applied 

 to the direction of the spiral in 

 certain shells when they turn to 

 the left: sinistrorse, a., sin'-is- 

 trdrs', in bot., applied to a spiral 

 directed towards the left. 



sinuate, a., sm'u-dt, also sinuated, 

 a., sin'-u-dt'&d (L. sinudtum, to 

 swell out in curves from sinus, 

 a bent surface, a curve), in bot., 

 cut so as to have a broken and 

 wavy margin, as the margin of 

 a leaf: sinuous, a., sin'-U'US, 

 tortuous ; having a wavy or 

 flexuous margin, as a leaf. 



sinus, n., sln'us, (L. sinus, a 

 bent surface, a curve), in anat., 

 a cavity in a bone wider at the 



bottom than at the entrance ; in 

 surg., an elongated cavity con- 

 taining pus ; a dilated vein or 

 blood receptacle ; in bot. , a groove 

 or cavity; the indentation or 

 recess formed by the lobes of 

 leaves : sinuses, n. plu., sin'uz-es, 

 hollows or cavities, as in the 

 bones, or in the dura - mater : 

 sinus pocularis, pdk'ul'dr'-is (L. 

 poculum, a cup or goblet), a cup- 

 like cavity in the male urethra- 

 leading into the prostatic vesicle : 

 s. rhomboidalis, rdrnf-bdyd-al'-is 

 (L. rhombdides, a rhomboid 

 from L. rhombus, a rhombus, and 

 Gr. eidos, resemblance), a lozenge- 

 shaped cavity at the hinder ex- 

 tremity of the medullary canal : 

 s. terminalis, term.'-fa-a$b (L. 

 termindlis, terminal from term- 

 inus, a boundary), a venous canal 

 encircling the vascular area in 

 the embryo : s. urogenitalis, ur- 

 o-jen-it-dl'is (Gr. ouron, urine ; 

 L. g$mtdlis, generative), a sinus 

 situated in front of the termina- 

 tion of the intestine forming a 

 separation, which produces a dis- 

 tinct passage for the genito- 

 urinary organs, formerly opening 

 into a cloaca : s. venosus, ven- 

 oz'us (L. venosus, full of veins 

 from vena, a vein), the main 

 portion of the auricles of the 

 heart, as distinguished from the 

 auricular appendages : osseous 

 sinuses, cavities in bones con- 

 taining air : venous sinuses, 

 hollows in the membrane of the 

 dura - mater of the brain, which 

 contain blood serving the purpose 

 of veins. 



siphon, n., sif-tin (Gr. siphon, L. 

 sipho, a hollow reed or tube), a 

 bent pipe or tube whose arms are 

 of unequal length, chiefly em- 

 ployed to draw off liquids from 

 casks, etc. ; applied to the re- 

 spiratory tubes in the Mollusca, 

 and to other tubes of different 

 functions : siphonium, n., sif-onl 

 i- um t a bony air- tube in some birds. 



