sient
sient is a Latin form of sum, meaning “be, exist; (as auxiliary) is, are, was”. It is the 3rd person plural present active subjunctive.
Found 50 times in the Latin texts on Socratos.
Where it is used
Cicero, Orator 157: … utum usitate. Itaque utrumque Terentius: eho tu, cognatum tuom non noras? post idem Stilponem inquam noveras. Sient plenum est, sint imminutum; licet utare utroque. Ergo ibidem: quae quam sint cara post carendo intellegunt, q …
Terence, Andria 1.5.288: Et ad pudicitiam et ad rem tutandam sient.
All forms of sum (conjugation table)
Source: Socratos (socratos.org), a free reader for Ancient Greek and Latin. Grammar from the Perseus Treebank and Morpheus; dictionary entries from Lewis & Short, A Latin Dictionary (Perseus Digital Library, CC BY-SA). Counts are from the texts on Socratos.