The only free and comprehensive online etymological dictionary of the Spanish language
ventana f. (Noun) "window"

The modern meaning of window dates to very early 15th cent. Prior meaning was "vent" (c. 1250) and "nostril" (14th cent.). From Latin *ventana 'id.,' from Latin ventus "wind" (see viento).
Venus f. (Noun) "Venus"

A learned borrowing from Latin Venus 'id.' From Proto-Italic *wenos- 'id.' From Proto-Indo-European *u̯enh1- "to desire."

Indo-European: Germanic: Gothic wens "hope," Old Norse ván "opinion," Old High German wān 'id.,' Old Saxon wān "expectation," Old English wān "opinion;" Albanian: ũn "hunger;" Tocharian: A wañi "joy," B wīna 'id.;' Indo-Iranian: Sanskrit vánate "he desires," Young Avestan vaṇtā- "wife;" Anatolian: Hittite u̯en-zi "to copulate"
ver (Verb) "to see"

12th cent. Old Spanish veer. Form Latin videre 'id.' From Proto-Italic *wid-ē- 'id.' From Proto-Indo-European *u̯id-eh1- "to see." From the root *u̯ei̯d- "to see," "to know."

Romance: Western Vulgar Latin: Asturian ver, Portuguese ver, Galician ver, Catalan veure, French voir, Itailan vedere ; Eastern Vulgar Latin: Aromanian ved, Romanian vedea ; Sardinian: biri

Italic: South Picene videtas "you see"

Indo-European: Celtic: Old Irish ro-finnadar "to find out;" Germanic: Gothic witan "to know," Old Norse vita "," Old High German wizzan "," Old Saxon witan 'id.,' Old English witan 'id.' (English to wit); Balto-Slavic: Old Church Slavonic věděti "to know," Russian védat' "to manage," Czech věděti "to know," Polish wiedzieć 'id.,' Slovene vẹ́dẹti 'id.,' Old Prussian waist 'id.;' Hellenic: Ancient Greek εἰδέναι (eidémai) "to know;" Armenian: egit "he found;" Indo-Iranian: Sanskrit ved- "to find," Old Avestan vīnastī "he finds"
verano m. (Noun) "summer"

11th cent. From Vulgar Latin tempus veranum "spring season." The Latins did not distinguish the spring and summer seasons as we do today, and in all the Romance languages the word came to mean summer. In Old Spanish, verano continued to mean spring, and estío being the word for summer, until after the Golden Age. For the etymology of tempus, see tiempo. Veranum comes from Latin ver "spring." From Proto-Italic *wes- 'id.' From Proto-Indo-European *u̯es-r/n- 'id.'

Romance: Western Vulgar Latin: Asturian veranu, Portuguese verão, Galician verán ; Eastern Vulgar Latin: Aromanian vearã, Romanian vară

Indo-European: Celtic: Middle Irish errach "spring," Old Welsh guiannuin 'id.,' Old Cornish guaintoin 'id.;' Germanic: Old Norse vár "spring," Old Frisian wars 'id.;' Balto-Slavic: Old Church Slavonic vesna "," Russian vesná 'id.,' Czech vesna 'id.,' Polish wiosna 'id.,' Slovene vẹ̑sna 'id.,' Lithuanian vãsara "summer," Latvian vasara 'id.;' Hellenic: Ancient Greek ἔαρ (héar) "spring;" Armenian: garown "spring;" Indo-Iranian: Sanskrit vasantá- "spring," Avestan vaŋri "in spring"
verdad f. (Noun) "truth"

12th cent. From veritatem, accusative of veritas 'id.' From verus "true" (see vero (2)).

Romance: Western Vulgar Latin: Asturian verdá, Portuguese verdade, Galician verdade, Catalan veritat, French vérité, Italian vertà
verdadero (Adjective) "true"

11th cent. From verdad. It replaced the original word: vero (2).
verdadero (Adjective) "true"

11th cent. From verdad.
verde m. (Adjective, Noun) "green;" "unripe;" "inexperienced"

11th cent. From Latin viridis "green;" "young." From virere "to be green," "to sprout." From Proto-Italic *weis- 'id.' From Proto-Indo-European *u̯ei̯s- "to sprout."

As a surname, it was first applied to as a nickname in the medieval period, denoting youth and vigor.

Romance: Western Vulgar Latin: Asturian verde, Portuguese verde, Galician verde, Catalan verd, French vert, Italian verde ; Eastern Vulgar Latin: Aromanian vearde, Romanian verde ; Sardinian: birde

Indo-European: Germanic: Old Norse vísir "sprout," Old High German wīsa "meadow," Old English wīse "sprout;" Balto-Slavic: Old Prussian wēisin "fruit," Lithuanian veĩsti "to breed;"
vergüenza f. (Noun) "shame"

12th cent. From Latin verecundia "shame;" "modesty." From verecundus "ashamed;" "modest." From the verb vereri "to revere." From Proto-Italic *wer-ē- 'id.' From Proto-Indo-European *u̯er-eh1- "to sense." De Vaan (2014) suggests a semantic evolution of "to sense" into "to be wary" to "to show respect."

Romance: Western Vulgar Latin: Asturian vergoña, Portuguese vergonha, Galician vergoña, Catalan vergonya, French vérécondie, Italian vergogna ; Sardinian: bergugna

Indo-European: Celtic: Old Irish cóïr "just," Old Welsh couer "complete;" Germanic: Gothic wars "careful," Old Norse varr 'id.,' Old High German gi-war 'id.,' Old Saxon war 'id.,' Old English wær 'id.' (English aware); Balto-Slavic: Latvian vẽrt "to watch;" Tocharian: A wär- "to smell," B wär-sk- 'id.'
verificar (Verb) "to verify"

16th cent. Borrowed from Medieval Latin verificare 'id.,' a learned form from verus "true" and facere "to do." See vero (2) and hacer respectively for continued etymologies.

Romance: Western Vulgar Latin: Portuguese verificar, Galician verificar, French vérifier, Italian verificare ; Eastern Vulgar Latin: Romanian verifica