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

12th cent. From Latin noctem, accusative case of nox 'id.' From Proto-Italic *nok-t- 'id.' From Proto-Indo-European *nógwh-t- 'id.'

Romance: Western Vulgar Latin: Asturian nueche, Portuguese noite, Galician noite, Catalan nit, French nuit, Italian notte ; Eastern Vulgar Latin: Aromanian noapti, Romanian noapte ; Sardinian: noti

Indo-European: Celtic: Gaulish nox "night," Old Irish innocht "tonight," Old Welsh he-noid 'id.,' Middle Breton hanoez 'id.,' Cornish haneth 'id.;' Germanic: Gothic nahts "night," Old Norse nǫ́tt 'id.,' Old High German naht 'id.,' Old Saxon naht 'id.,' Old English næht 'id.' (English night); Balto-Slavic: Old Church Slavonic noštь "night," Russian noč' 'id.,' Czech noc 'id.,' Polish noc 'id.,' Slovene nọ̑č 'id.,' Old Prussian naktin 'id.,' Lithuanian naktìs 'id.,' Latvian nakts 'id.;' Albanian: natë "night;" Hellenic: Ancient Greek νύξ (nyks) "night;" Indo-Iranian: Sanskrit nákt- "night;" Tocharian: B nekcīye "at night;" Anatolian: Hittite neku-zi "to become night"
nombre m. (Noun) "name;" "noun"

12th cent. Old Spanish nomne, from Vulgar Latin *nomine, from Latin nomen 'id.' From Proto-Italic *nōm-n- 'id.' From Proto-Indo-European *h3neh3-mn- 'id.'

Dialect Variants: 11th cent. Old Spanish nomen, Colunga nome

Romance: Western Vulgar Latin: Asturian nome, Portuguese nome, Galician nome, Catalan nom, French nom, Italian nome ; Eastern Vulgar Latin: Aromanian numã, Romanian nume ; Sardinian: nomene

Italic: Oscan numneís "of the name," Umbrian numen "name"

Indo-European: Celtic: Gaulish anuana "name," Old Irish ainm 'id.,' Old Welsh anu 'id.,' Middle Breton hanu 'id.,' Cornish enw 'id.;' Germanic: Gothic namo "name," Old Norse nafn 'id.,' Old High German namo 'id.,' Old Saxon namo 'id.,' Old English nama 'id.' (English name); Balto-Slavic: Old Church Slavonic imę "name," Russian ímja 'id.,' Czech jméno 'id.,' Polish imię 'id.,' Slovene imę̑ 'id.,' Old Prussian emmens 'id.;' Albanian: emër "name;" Hellenic: Ancient Greek ὄνομα (ónoma) "name;" Phrygian: onoman "name;" Armenian: anown "name;" Indo-Iranian: Sanskrit nā́man- "name," Avestan nāman- 'id.;' Tocharian: A ñom "name," B ñem 'id.;' Anatolian: Hittite lāman- "name," Hieroglyphic Luwian álaman- 'id.,' Lycian alãman- 'id.'

Compare dialect variant Colunga nome and textual variant Fuero de Avilés nomen (11th cent.) which seem to preserve the middle vowel in Vulgar Latin *nomine.

The Indo-Europeans ritualized the application of a name to a newborn and in Proto-Indo-European, the phrase for naming a newborn was "to make a name." A mother of a newborn was given nine days to recover, then after she would name the child for his or her name-day.
nona f. (Noun) "grandma"

13th cent. Borrowed from Latin nonna "old woman," "wet nurse." Also note 12th cent. Old Spanish nana "married woman."

Romance: Western Vulgar Latin: French nonne, Italian nonna

Despite the semantic argument that the word is native to Spanish, and not borrowed from Latin, the word did not undergo palatalization. Fascinatingly, a cousin of the word is ñoño, which palatalized twice - generally against the norm in Spanish.
norma f. (Noun) "rule"

17th cent. borrowing from Latin norma "carpenter's square," but also "standard." Perhaps borrowed from Etruscan, which in turn borrowed from Ancient Greek γνώμων ‎(gnṓmōn) "judge."

Romance: Western Vulgar Latin: Portuguese norma, Italian norma

If norma does come from γνώμων, the ultimate etymology comes from PIE *ǵneh3- "to know" (see conocer for further discussion of this root).
normal (Adjective) "normal"

19th cent. From Latin normalis 'id.,' from Latin norma "carpenter's square," but also "standard" (see norma).

Romance: Western Vulgar Latin: Portuguese normal, French normal, Italian normale ; Eastern Vulgar Latin: Romanian normal
norte m. (Noun) "north"

Late 15th cent. Borrowed from Old French nort 'id.,' borrowed from Old English norþ (north). From Proto-Germanic *nurþera- 'id.' From Proto-Indo-European *h1n̥r-tero- 'id.'

Romance: Western Vulgar Latin: Asturian norte, Portuguese norte, Galician norte, Catalan nord, French nord, Italian nord ; Eastern Vulgar Latin: Romanian nord

Italic: Oscan nertrak "left," Umbrian nertru 'id.'

Germanic: North Germanic: Old Norse norðr "north;" West Germanic: Middle High German norder "north," English north

Indo-European: Hellenic: Ancient Greek ἔνεροι (éneroi) "those below;" Tocharian: B ñor "below"
nos (Personal Pronoun) "(to) us"

10th cent. From Latin nos "we," "us." From Proto-Italic *nōs 'id.' Taken from the accusative in Proto-Indo-European *nōs 'id.'

Romance: Western Vulgar Latin: Asturian nós, Portuguese nós, Galician nós, Catalan nós, French nous, Italian noi ; Eastern Vulgar Latin: Aromanian noi, Romanian noi ; Sardinian: nois
nosotros (Personal Pronoun) "we"

14th cent. From Old Spanish nós "we" and otros "others." See nos and otro respectively.
nota f. (Noun) "note;" "grade"

13th cent. From Latin nota "note." Probably originally meaning "sign" or "signal," as notare meant "to mark" (in order to be noticed). Of unknown origin.

Romance: Western Vulgar Latin: Portuguese nota, French note
noticia f. (Noun) "message;" "news," "piece of news"

13th cent. From Latin notitia "fame," "notice." From notus "known," the passive participle of noscere "to know" (see conocer for further etymology).

Romance: Western Vulgar Latin: Portuguese notícia, French notice