extit.isse V 1 1 PERF ACTIVE INF 0 X
exto, extare, extiti, - V (1st) [XXXDX] lesser
stand out or forth, project be visible, exist, be on record;
Syncope s/x => +is
Syncopated perfect sometimes drops the 'is' after 's' or 'x'
existit.isse V 3 1 PERF ACTIVE INF 0 X
existo, existere, existiti, existitus V (3rd) [XXXDX] lesser
step forth, appear; arise; become; prove to be; be (Bee);

Credits:
This, our local install of the popular standby Whitaker's Words, is possible thanks to the resurrection of the venerable project at William Whitaker's Words, where you will also find extensive documentation. The corresponding GitHub repository is where you can submit issues about missing forms and analyses.
This web interface by Walter M. Shandruk.