en un tris 30
He was about to refer the query to the entries in ( preposition ) , a ( article ) , tris ( "something slight, very short span, little noticeable fact") ; but it turns out that for the RAE the correct definition is that provided by CARLOS V. CICOTTINO, which makes it a locution, since it would have a meaning of its own. And I do not know the origin, but it would be good to understand how it went from inane to pernicious; unless the phrase is incomplete and is actually "in a tris of [some risky situation]". See synonym/tris, tris after .