v. have, was (indicates past and present perfect tenses)

Wo lost fron wah ney dov, ahrk fin reyliik do jul … Ahrk fin Kel lost prodah, do ved viing ko fin krah ...
Who was kin to both wyrm, and the races of man … And the Scrolls have foretold, of black wings in the cold ...
(Book, Songs of Skyrim)

Zeymahi lost ont du'ul Bormahu.
My brother was once the crown of our father
(Paarthurnax, 0009C213)

Zu'u lost kriaan hi ont
I've killed you once.
(Alduin, 000ED365)

Lost funt.
(You) have failed.
(Paarthurnax, 00044C4F)

From los ‘is’.

Can be omitted when the sense is clear, as in Zu'u uth nall [sic] thurri [sic] ‘I (was) ordered by my lord’ (000E16FA), Alduin mah ‘Alduin (has) fallen’ (000E16FD). Not used in the sense “possess, contain”. See instead piraak.