The only free and comprehensive online etymological dictionary of the Spanish language
hermano (Noun) "sibling"

10th cent. Old Spanish ermano; 11th cent. hermana. From Latin hermanus 'id.,' from germanus 'id.' From the phrase frater germanus "brother of the same father or mother" and its female counterpart soror germana. For the etymology of frater, see fraile; for the etymology of germanus, see germen.
hermoso (Adjective) "beautiful"

Early 12th cent. Old Spanish fuermoso. From Latin formosus 'id.,' from forma "form," "beauty" and -osus (see forma and -oso respectively).

Also the origin of several surnames, including Hermoso, Hermosa, Hermosel, Hermosilla, Hermosín, Hermozin, and Ricohermoso.

Romance: Western Vulgar Latin: Asturian formosu, Portuguese formoso, Galician fermoso, Catalan formós, Italian formoso; Eastern Vulgar Latin: Romanian frumos
héroe m. (Noun) "hero"

Late 15th cent. From Latin heroem, accusative of heros 'id.' Borrowed from Ancient Greek ἥρως ‎(heros) 'id.' Of unknown origin. Presumably borrowed from a non-Indo-European language.

Romance: Western Vulgar Latin: Portuguese herói, French héros, Italian eroe; Eastern Vulgar Latin: Romanian erou
hiel f. (Noun) "gall," "bile"

13th cent. From Latin fel 'id.,' from an unattested pre-form *fell (perhaps under influence from mel "honey"). From Proto-Italic *fell "bile," "yellow." The word is a bit of a "Italic" mystery. The appurtanance of *f- in Proto-Italic points to *gwh- or *bh- in Proto-Indo-European, yet in all other languages we see signs the original sound was *ǵh-. One "solution" proposed is that one of the dialects within Italic underwent a sound change *ǵh to *f; while the dialect did not survive, the word *fell managed to outlive the dialect and replaced the native word (de Vaan 2014). As one can see, this proposal is hardly convincing; yet linguists are left without a better explanation. Therefore, the assumed proto-form in Indo-European is *ǵhelh3-n̥- "yellow."

Romance: Western Vulgar Latin: Asturian fiel, Portuguese fel, Catalan fel, French fiel, Italian fiele ; Eastern Vulgar Latin: Aromanian heari, Romanian fiere ; Sardinian: febi, fele

Indo-European: Proto-Germanic: Old Norse gall "gall," Old High German galla 'id.,' Old Saxon galla 'id.,' Old English gealla 'id.' (English gall); Balto-Slavic: Old Church Slavonic zlьčь "bile," Russian žëlč' 'id.,' Czech žluč 'id.,' Bulgarian zlăč 'id.,' Lithuanian tulžìs 'id.,' Latvian žul̂(k)ts 'id.;' Hellenic: Ancient Greek χόλος (khólos) "bile," "wrath;" Indo-Iranian: Avestan zāra- "bile"
hielo m. (Noun) "ice"

13th cent. From Latin gelus "frost." From Proto-Italic *gelu- 'id.' From Proto-Indo-European *ǵel-u̯-

Indo-European: Germanic: Gothic kalds "cold," Old Norse kaldr 'id.,' Old High German kalt 'id.,' Old Saxon kald 'id.,' Old English ceald (English cold); Balto-Slavic: Old Church Slavonic xladъ "cool breeze," Russian xólod "cold"
hijo (Noun) "son," "daughter"

11th cent. Old Spanish fijo. From Latin filius 'id.,' Old Latin filios. From Proto-Italic *filio- 'id.' From Proto-Indo-European *dhh1i̯-l- 'id.' From *dheh1- "to suckle." See also felíz.

Romance: Western Vulgar Latin: Asturian fíu, Portuguese fillo, Galician fillo, Catalan fill, French fils, Italian figlio; Eastern Vulgar Latin: Aromanian hilj

Italic: Umbrian fel, Faliscan fileo, Venetic filia "daughter"
historia f. (Noun) "history," "story"

A 13th cent. borrowing direct from Latin historia 'id.' Borrowed by the Latins from Greek ἱστορία (historía) 'id.' From ἵστωρ (hístor) "wise man," "expert." From Proto-Indo-European *u̯id-tōr- "knower." From the root *u̯ei̯d- "to know," "to see" (whence ver).

Romance: Western Vulgar Latin: Asturian historia, Portuguese história, Catalan història, French histoire, Italian storia; Eastern Vulgar Latin: Romanian istorie

Hellenic: Boeotian ϝίστωρ (wístor)
hogar m. (Noun) "home;" "hearth"

The sense of hearth is original. From Vulgar Latin *focaris 'id.,' from Latin focus "fire" (see fuego).

Romance: Western Vulgar Latin: Portuguese fogo, Galician fogo, Catalan foc, French feu, Italian fuoco; Eastern Vulgar Latin: Aromanian foc, Romanian foc; Sardinian fogu
hoja f. (Noun) "page," "sheet of paper"

Old Spanish foja. From Latin folia "leaves." Originally a neuter plural noun (sing. folium) but reanalyzed as a feminine singular on the basis of the -a ending. From Proto-Italic *folio- "leaf." From Proto-Indo-European *dholH-i̯o- 'id.'

Also the origin of the surnames Hojo, Hojas, Hojeda, and Hojedo.

Romance: Western Vulgar Latin: Asturian fueya, Portuguese folha, Galician folla, Catalan fulla, French feuille, Italian foglia; Eastern Vulgar Latin: Aromanian foalji, Romanian foaie; Sardinian: fógiu

Indo-European: Celtic: Gaulish pempe-doula "Pontentilla" (lit. 'five-leaves'), Middle Irish duilne "leaf," Middle Welsh deil "foliage," Old Breton dol "leaves," Old Cornish delen "leaf;" Germanic: Old English dile "dill" (English dill); Albanian: dal "I emerge;" Armenian: dalar "green;" Hellenic: Ancient Greek θάλος (thálos) "sprout;"
hola (Interjection) "hello"

16th cent. Probably from French holà "stop there," a compound of ho "stop" and "there."