The unexpected loss ofc may be explained as a metanalysis of the negativenēcubi, where thec was interpreted as being fromnec (truly here the negation was just thenē). This is also clear in the compoundalicubi andsī-cubi. Contamination withibi(“there”) is also possible.
“[...] saevusubi Aeacidae tēlō iacet Hector,ubi ingēns Sarpēdōn,ubi tot Simois correpta sub undīs scūta virum galeāsque et fortia corpora volvit!”
“[Troy…],where fierce Hector lies, [pierced] by the spear of Achilles,where huge Sarpedon [perished], [and]where the [River] Simois has seized and rolled beneath its waves so many shields, helmets and bodies of brave men!” (The repetition of “ubi” exemplifiesanaphora. “Aeacidae” is apatronymic:Achilles was the grandson “ofAeacus.” Readvirorum for virum, a syncopated genitive plural. See also:Simois orSimoeis;Sarpedon.)
The adverbsubī̆(“where”),ubī̆nam(“where in the world?”),ubī̆cumque(“wherever”) andubiubī̆ are sometimes used with the genitive ofterra(“land”) (plural:terrārum),locus(“place”) (singular:locī, plural:locōrum),gens(“nation”) (plural:gentium), to denote the same meaning as "where on earth". "in what country" or "where in the world":
Ubi terrarum esses, ne suspicabar quidem!
Where on earth could you be, I didn't even mistrust you!
Ubi terrarum est?
Where on earth is he?
Quid ageres,ubi terrarum esses.
What will you do,where in the world should you be?
Ubi terrarum sumus?
Where in the world are we?
Ubi illum quaeram gentium?
Where in the world should I search for him?
Ubi loci fortunae tuae sint, facile intellegis.
You realize with easewhere on earth your fortunes may be.
Ubi terrarum aut maris fuisti?
Where on earth or sea have you been?
Non edepol nunc,ubi terrarum sim, scio, si quis roget.
Heavens, I know not now,where in the world I may be, if anyone asks.
Carl Meißner; Henry William Auden (1894),Latin Phrase-Book[1], London:Macmillan and Co.
when it was day:ubi illuxit, luxit, diluxit
Sihler, Andrew L. (1995),New Comparative Grammar of Greek and Latin, Oxford, New York: Oxford University Press,→ISBN
Ritschl, Friedrich (1870), “cubi =ubi und Verwandtes.”, inRheinisches Museum für Philologie (in German), volume25,pages306–312 =Ritschl, Friedrich (1870), “cubi = ubi und Verwandtes bei Plautus.”, inFriedrich Ritschl’s Kleine Philologische Schriften (in German), volume III, published1877,pages135–143
^De Vaan, Michiel (2008), “ubī”, inEtymological Dictionary of Latin and the other Italic Languages (Leiden Indo-European Etymological Dictionary Series; 7), Leiden, Boston: Brill,→ISBN,page636