dis·ten·sion also dis·ten·tion 
(dĭ-stĕnshən)
(dĭ-stĕnshən)n.
The act of distending or the state of being distended.
[Middle English distensioun, from Old French, from Latin distēnsiō, distēnsiōn-, alteration of distentiō, from distentus, past participle of distendere, to distend; see DISTEND.]