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-uelo, -elo, -illo, -iello, -el Diminutive suffix.

From Latin -olus, -ellus, -illus, -lus 'id.' All from original Latin suffix -ulus 'id.' The vowel changes and consonant additions were due to sound conditioning. From Proto-Italic *-elos. From Proto-Indo-European *-elo- 'id.'

Romance: Western Vulgar Latin: Asturian -uelu, Portuguese -ulo, Galician -ulo, Catalan -ul, French -ule, Italian -olo; Eastern Vulgar Latin: Romanian -ul

Italic: Oscan kaíla "sacred building" (kaχ-elā-), Faliscan cela "small storeroom" (kēl-elā-)

Indo-European: Celtic: Welsh -el, Breton -el; Germanic: Old Icelandic -ull, Old English -l, Old High German -ala,
uh (Interjection) "ugh"

Of expressive origin. No further etymology possible.
últimamente (Adjective) "lastly"

From ultimo and -mente, an adjective-forming suffix.
ultimar (Verb) "to finish"

17th cent. From Latin ultimare 'id.,' from ultimus "last" (see último).
último (Adjective) "last," "final"

15th cent. From Latin ultimus 'id.' From Proto-Italic *ol-tamo 'id.,' from Proto-Indo-European *h2ol-tmHo- "furthest." From the root *h2el- "that" (see el (2), él).

Romance: Western Vulgar Latin: Portuguese último, Catalan últim, French ultime, Italian ultimo ; Eastern Vulgar Latin: Romanian ultim

Italic: Oscan últiumam "last"

An ancient comparative with *h2ol-tero- "further" (whence ultra).
ultra (Adverb) "beyond"

15th cent. From Latin ultra 'id.' From Proto-Italic *ol-tero- 'id.,' from Proto-Indo-European *h2ol-tero- "further." From *h2ol- "that" (see el (2), él).

Romance: Western Vulgar Latin: Portuguese ultra, French outre, Italian oltra

An ancient comparative with *h2ol-tmHo- "furthest" (whence último).
umbría f. (Adjective, Noun) "shady;" "shady place"

From Latin umbra "shadow." From Proto-Italic *unfrā- 'id.' Perhaps from Proto-Indo-European *Hu̯nskr-eh2- 'id.' but the phonology and semantics are troubling and the putative root *Hu̯enk- is uncertain.

Romance: Western Vulgar Latin: Asturian sombra, Portuguese sombra, Catalan ombra, French ombre, Italian ombra ; Eastern Vulgar Latin: Aromanian umbrã, Romanian umbră ; Sardinian: umbra

Indo-European: Balto-Slavic: Lithuanian unksmė̃ "shade"
un (Indefinite Article) "a"

An apocopated form from uno.

Romance: Western Vulgar Latin: Asturian unu, Portuguese um, Galician un, Catalan un, French un, Italian uno ; Eastern Vulgar Latin: Aromanian un, Romanian unu ; Sardinian: unu
uni- Prefix "one"

From Latin uni- 'id.' From unus "one" (see uno).
único (Adjective) "only," "unique"

Late 15th cent. From Latin unicus 'id.' From unus "one" (see uno and -icus, diminutive sufix (see -ico).

Romance: Western Vulgar Latin: Portuguese único, Catalan únic, French unique