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Webster 1913 Edition
Xiphiplastron
‖
Xiph′i-plas′tron
,Noun.
pl. 
Xiphiplastra
. [NL., fr. Gr. 
ξίφοσ 
a sword + plastron
.] (Anat.) 
The posterior, or fourth, lateral plate in the plastron of turtles; – called also 
xiphisternum
.