The Collaborative International Dictionary
Exitial
Exitial \Ex*i"tial\, Exitious \Ex*i"tious\, a. [L. exitialis,
exitious, fr. exitium a going out, a going to naught, i. e.,
ruin, fr.exire to go out: cf. F. exitial.]
Destructive; fatal. [Obs.] ``Exitial fevers.''
--Harvey.
Wiktionary
exitial
a. (context obsolete English) destructive; fatal