ubi

For cubī with iambic shortening, from Proto-Italic *kʷuðei or *kʷuβei, from Proto-Indo-European *kʷudʰei or *kʷobʰí (when compared with Hittite ku-wa-pi), from pronominal root *kʷu- + *-dʰi (“locative suffix”). Compare Ancient Greek πόθι (póthi). See also the same meanings in quō.^[1]

The unexpected loss of c may be explained as a metanalysis of the negative nēcubi, where the c was interpreted as being from nec (truly here the negation was just the nē). This is also clear in the compound alicubi and sī-cubi. Contamination with ibi (“there”) is also possible.

Pronunciation

(Classical Latin) IPA^(key): /ˈu.bi/, [ˈʊbɪ]
(modern Italianate Ecclesiastical) IPA^(key): /ˈu.bi/, [ˈuːbi]
(Archaic, Poetic) IPA^(key): /ˈu.biː/, [ˈʊbiː]
(Archaic, Poetic) IPA^(key): /ˈu.bi/, [ˈuːbi]

Adverb

ubi or ubī (not comparable)

(interrogative) where? in what place?, in which place?
Ubi?

Where?

Ubi patera nunc est? — In cistulā.

Where is the bowl now? — In the small chest.

Ubi inveniam Pamphilium? Ubi quaeram?

Where can I find Pamphilus? Where should I look?

Ubi sum?

Where am I?

Nesciō ubi sim.

I don't know where I am.

Īcare, ubi es?

Icarus, where are you?

(relative) where or in a place where [ quotations ▼]
Ubi tyrannus est, ibi plane est nulla res publica.

Where there is a tyrant, there is clearly no republic.

(relative) when
Ubi carceri appropinquavit, portam apertam vidit. (Cambridge Latin course 3)

When he approached the jail, he saw the open gate.

(of time) as, as soon as, whenever, when
(informal) in which, by which, with which; by whom, with whom

Usage notes

The adverbs ubī̆ (“where”), ubinam (“where in the world?”), ubī̆cumque (“wherever”) and ubiubi are sometimes used with the genitive of terra (“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 ease where 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.

[1