The Collaborative International Dictionary
Non est inventus
Non est inventus \Non` est` in*ven"tus\ [L., he is not found.]
(Law)
The return of a sheriff on a writ, when the defendant is not
found in his county.
--Bouvier.
Wiktionary
non est inventus
phr. (context legal English) The response of a sheriff on a writ, when the defendant is not found in his county.