Note: The above etymology of Latin servus "slave" is carefully argued by Helmut Rix (Die Termini der Unfreiheit in den Sprachen Alt-Italiens, Stuttgart, 1994, pp. 54-88), who rejects claims that the word is of Etruscan origin. Rix hypothesizes that between about 700 b.c. and 450 b.c., as most transhumant shepherds in the Italian peninsula came to be slaves, an agent noun meaning "flock guard" developed a secondary sense "slave," and by the time of the earliest Latin texts had largely lost its original meaning (with pāstor becoming the usual word for a shepherd—see pastor entry 1). The presumption is that Italic languages—as Indo-European languages generally—lacked a word for "slave," as slavery was an institution endemic to older Mediterranean and Middle Eastern civilizations. Note that Umbrian has a verb exemplified by the imperative seritu "(let him/her) protect!" that corresponds in form but not in sense to Latin servīre, which had been repurposed to reflect the new meaning of the noun *seru̯os. Rix hypothesizes that the Latin verb servāre "to watch over, look after" originally meant exclusively "to watch (the skies for an omen)," as a derivative of a noun *seru̯ā or *seru̯om "observation (of the skies)," and suggests that its senses expanded to cover those formerly held by the repurposed verb servīre.