A DICTIONARY 



ABU 



A. In words of Greek derivation, A 

 is used privatively, or in a negative 

 sense ; as acephalous, without a 

 head ; acaulous, having no stem ; 

 apetalous, having no petals; aco- 

 tyledonous, having no cotyledons, 

 &c. 



ABARTICTJLA'TION. (from db and arti- 

 culatio, Lat.) That kind of articu- 

 lation which admits of manifest 

 motion ; it is also called diarthro- 

 sis, from the Greek word SidpOpwai s, 

 and dearticulation. 



ABBREVIATED, (abbreviatus, Lat.) 



1 . In botany, an epithet for the 

 perianth. An abbreviated perianth 

 is shorter than the tube of the 

 corolla, as in Pulmonaria maritima. 



2. Shorter than a correspondent 

 part. 



ABDO'MEN. (abdomen, Lat. abdomen, 

 Fr. dbdomine, It.) The large cavity 

 commonly known as the belly, 

 containing the organs more imme- 

 diately concerned in the process of 

 digestion, as the stomach, liver, 

 spleen, pancreas, bowels, &c. 



ABDO'MINAL. (from abdomen.) 



1 . Pertaining to the abdomen or 



belly. 



2 Fishes belonging to the order 



abdominales, or the fourth order of 



Linnaeus. 



ABDOMINA'LES. The fourth order of 

 fishes in the arrangement of Lin- 

 naeus; they have ventral fins be- 

 hind the thoracic, or fins placed on 

 the belly, and the branchia ossicu- 



lated; they chiefly inhabit fresh 

 water. The salmon, trout, smelt, 

 &c., are examples. 



ABDU'CENT. (from alduco, Lat.) The 

 name given to those muscles which 

 serve to open or draw back parts 

 of the body; their opposites, or 

 antagonists, are called adducent. 



ABDTTC'TOR. (abducteur, Fr. alduttore, 

 It.) The same as abducent. 



ABERRA'TIOIT. (abberatio, Lat.) 



1. A certain deviation in the rays 

 of light, from the true or geometri- 

 cal focus of reflection or refraction, 

 in curved specula or lenses. 



2. A deviation from the ordinary 

 course of nature. 



ABNO'RMAL. | abnormis, Lat.) Ir- 



ABNO'RHOTJS. j regular; unwonted; 

 unnatural. 



ARNO'RMITY. Departure from natural 

 formation ; irregularity. 



ABRA'NCHIA. (from a, priv. and 

 (3pd^W a , Grr.) Animals destitute 

 of gills, and having no apparent 

 external organs of respiration. 



ABRANCHIA'TA. The third order of 

 articulata, having no apparent ex- 

 ternal organs of respiration, but 

 seeming to respire, some, by the 

 entire surface of the skin, others, 

 by internal cavities. The abran- 

 chiata are divided into two families ; 

 the - first, Abranchiata setigera, 

 comprising the Lumbrici and Nai- 

 des of Linnaeus; the second, Abran- 

 chiata asetigera, comprising the 

 Hirudo and Gordius of Linnaeus. 



