GLOSSARY. 



143 



Pom'pholyx (Gr. 



bubble). A disease of the skin. 



Poplite'al (Lat. po'ples, the ham) be- 

 longing to the ham. 



Pore (Gr. iropos, por'os, a means of 

 passing). In natural philosophy, 

 an interstice or minute space be- 

 tween the molecules of matter. 



Po'rism (Gr. iropifa, pori'zo, I bring 

 about). In geometry, a proposition 

 affirming the possibility of finding 

 such conditions as will render a 

 certain problem indeterminate or 

 capable of innumerable solutions. 



Porosity (Gr. iropos, por'os, a pore). 

 The state of having pores : in na- 

 tural philosophy, the quality of 

 bodies in virtue of which their con- 

 stituent atoms are separated by va- 

 cant spaces or pores. 



Porous (Gr. Tropos, por'os, a pore). 

 Having pores or interstices. 



Por'phyry (Gr. vopQvpa, por'pJiura, 

 purple dye). Originally, a reddish- 

 igneous rock : now used in geology 

 to denote any rock containing im- 

 bedded crystals distinct from the 

 main mass. 



Por/tal (Lat. por'ta, a gate). In ana- 

 tomy, belonging -to the transverse 

 fissure of the liver, called by old 

 anatomists the porta or gate of the 

 organ. 



Posses'sive (Lat. possid'eo, I possess). 

 In grammar, the case of nouns which 

 denotes possession, or some relation 

 of one thing to another. 



Post- (Lat.) A Latin preposition used 

 in the composition of many words, 

 and signifying after or since. 



Postdilu'vian (Lat. post, after ; di- 

 lu'vium, a deluge). Living after 

 the deluge. 



Posterior (Lat. later). Later : a pos- 

 terio'ri, a phrase signifying "from 

 what follows," applied to an argu- 

 ment used to infer a cause or 

 antecedent from an effect or conse- 

 quent. 



Postfron'tal (Lat. post, after; from, 

 the forehead). Behind the frontal 

 bone. 



Postmeridian (Lat. post, after ; me- 

 ri'dies, midday). Belonging to the 

 afternoon. 



Post Mortem. (Lat.) After death. 



Postpositive (Lat. post, after ; pono, 

 I put). Placed after. 



Postulate (Lat. pos'tulo, I demand). 

 A position or supposition con- 

 sidered too plain to require illus- 

 tration ; it differs from an axiom 

 only in being put as a request in- 

 stead of an assertion. 



Potential (Lat. po'tens, able). Hav- 

 ing the power to impress the ideas 

 of certain qualities, though the 

 ideas are not inherent in the thing ; 

 existingin possibility ; iugrammar, 

 applied to the mood of verbs which 

 denotes capability or power. 



Prse- or Pre- (Lat. prce, before). A 

 preposition used in compound words, 

 signifying before or in front of. 



Praecor'dia (Lat. prce, before; cor, 

 the heart). The region of the body 

 in front of the heart. 



Prseflora'tion (Lat. prce, before ; Jlos, 

 a flower). The arrangement of the 

 parts of the flower in the flower-bud ; 

 the same as aestivation. 



Praefolia'tion (Lat. prce, before ; fo'- 

 lium, a leaf). The arrangement of 

 the leaves in a leaf-bud ; the same 

 as vernation. 



Praeno'men (Lat. prce, before ; no- 

 men, a name). Among the Ro- 

 mans, a name prefixed to the family 

 name, answering to our Christian 

 name. 



Pre- (Lat. prce, before). See Prse. 



Preces'sion (Lat. prce, before ; ce'do, 

 I go). A going before. In astro- 

 nomy, the precession of the equi- 

 noxes is a slow retrograde motion 

 which they undergo in a direction 

 contrary to the order of the sigqs, 

 and which makes them succeed each 

 other sooner than they otherwise 

 would have done. 



Precipitant (Lat. prce'ceps, headlong). 

 In chemistry, a substance which, 

 added to a solution of another, 

 causes the latter to be thrown down 

 to the bottom of the fluid. 



Precipitate (Lat. prce'ceps, headlong). 

 To throw down a substance from 

 its solution ; the substance thus 

 thrown down. 



Precor'dial (Lat. prce, before; cor, 



