The only free and comprehensive online etymological dictionary of the Spanish language
o (1) (Conjunction) "or"
10th cent. From Latin aut 'id.' From either *aut-i 'id.' in Proto-Italic. From Proto-Indo-European *h2eu̯ "away."
Indo-European
Romance
Asturian o, Portuguese ou, Galician ou, Catalan o, French ou, Italian o, Romanian au
Italic
Oscan aut "or," Umbrian ute 'id.'
Celtic
Old Irish úa "away," Old Welsh o 'id.,' Middle Breton o 'id.'
Balto-Slavic
Old Church Slavonic u- "from," Russian u- 'id.,' Polish u- 'id.,' Slovene u- 'id.,' Old Prussian au- 'id.,' Lithuanian au- 'id.,' Latvian au- 'id.'
Hellenic
Ancient Greek αὖ (aû) "again"
Indo-Iranian
Sanskrit áva "off," Old Avestan auuā 'id.'
-o (1) 1st person singular present ending.
From Latin -o 'id.' From Proto-Italic * 'id.' From Proto-Indo-European *-oh2, the thematic 1st person singular present ending.
o- (1), op- (Prefix) "power to help"
Not productive in Spanish. From Latin ops 'id.' From Proto-Italic *opi- 'id.' From Proto-Indo-European *h3ep-i̯- "force." From *h3ep- "to work," "to force."
Indo-European
Hellenic
Ancient Greek ὄμπνη (ómpen) "corn"
Indo-Iranian
Sanskrit ápnas- "property," Young Avestan -haṇt- "rich"
O (2) f. (Noun) "Virgin Mary;" any of the dates of the Advent Antiphons but especially "December 18th"
As the name for the Virgin Mary or the days of the O Antiphons in Catholicism, it comes from the frequent interjection O in the liturgical readings.
Responsible for the surname de la O.
-o (2) Forms masculine adjectives and nouns.
Earlier *-u a collapse into a single ending, drawn variously from Latin -us, nominative masculine ending, -um, nominative neuter and accusative masculine and neuter ending. From Proto-Italic *-os and *-om respectively. From Proto-Indo-European *-o-s and *-o-m, thematic nominative and accusative endings.
For feminine nouns with this ending, see -o (3).
o- (2), ob- Prefix "toward"
From Latin ob-, a grammaticalization of the preposition ob 'id.' From Proto-Italic *op 'id.' From Proto-Indo-European *h1opi̯ "at." Perhaps an ablaut of *h1epi̯ meant "on."
Indo-European
Italic
Oscan úp "at," Venetic op "from"
Balto-Slavic
Lithuanian api-
Hellenic
Ancient Greek ἔπι (épi) "on," Mycenaean e-pi- 'id.'
Armenian
Armenian ew "also"
Indo-Iranian
Sanskrit ápi "by," Avestan aipi 'id.'
On the word *h1opi̯, Sihler (1995) writes, "Some see in these forms various cases of an otherwise lost root-noun meaning literally 'back.' The 'on' sense may have something to do with pack animals or riding."
-o (3) Forms feminine nouns.
From Latin -us, feminine nominative ending. According to Penny (2002), the ending probably only survived in Old Spanish in mano as other modern Spanish feminine nouns ending in -o were learned additions drawn from Classical Latin. From Proto-Italic *-us 'id.' From Proto-Indo-European *-o-s, the thematic nominative ending, the same source of -o (2), which could be either masculine or feminine.
objetivo m. (Adjective, Noun) "objective"
18th cent. An adjectival from objeto.
objeto m. (Noun) "object"
15th cent. From Latin obiectus 'id.' From ob- "toward" (see ob-) and iacere "to throw" (see echar).
Indo-European
Romance
Portuguse objeto, French objet, Italian oggetto, Romanian obiect
obra f. (Noun) "work," "labor"
13th cent. From Latin opera "effort," from opus "work." From Proto-Italic *opes- 'id.' From Proto-Indo-European *h3ep-os 'id.'
Indo-European
Romance
Portuguese obra, Galician obra, Catalan obra, French œuvre, Italian opera, Romanian operă, Sardinianòbera
Italic
Oscan úpsed "he worked," úpsannúm "working," Umbrian opset "worked," Vestinian ośens "he worked," Paelignian upsaseter (subjunctive) "he worked," South Picene opesaúom "to work"
Germanic
Old Norse afl "power," Old Saxon ōƀian "to celebrate," Old High German uoben "to practice," Old English efnen "to perform"
Indo-Iranian
Sanskrit ápas- "work," Avestan huuāpah- "doing good work"