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Webster 1913 Edition
Desponsation
Desˊpon-sa′tion
,Noun.
 [L. 
desponsatio
: cf. OF. desponsation
.] A betrothing; betrothal. 
[Obs.] 
For all this 
desponsation 
of her . . . she had not set one step toward the consummation of her marriage. Jer. Taylor.
Webster 1828 Edition
Desponsation
DESPONSATION
,Noun.