The only free and comprehensive online etymological dictionary of the Spanish language
sangre m. (Noun) "blood"
12th cent. Old Spanish sangne, sangre. From Latin sanguinem, accusative of sanguis 'id.' From Proto-Italic *sanguen 'id.' From Proto-Indo-European *h1éh2-r- "blood." The suffix *-guen is of unknown meaning and unknown origin.
Indo-European
Romance
Asturian sangre, Portuguese sangue, Galician sangue, Catalan sangu, French sang, Italian sangue, Aromanian sãndzi, Romanian sânge, Sardinian sàmbani
Balto-Slavic
Latvian asins "blood"
Hellenic
Ancient Greek ἔαρ (héar) "blood"
Indo-Iranian
Sanskrit ásr̥j- "blood"
Tocharian
A ysār "blood," B yasar 'id.'
Old Spanish variant sangrue is anomalous. Perhaps under orthographic influence from Latin.
santo (Adjective, Noun) "holy;" "saint"
10th cent. From Latin sanctus 'id.' (Archaic Latin sakros "sacred"). From Proto-Italic *sank-to- "holy," but also "made safe." From Proto-Indo-European *sh2-n̥-k- "to secure," from earlier root *seh2k- 'id.'
San is from santo via apocopation.
Indo-European
Romance
Asturian santu, Portuguese santo, Galician santo, Catalan sant, French saint, Italian santo, Aromanian sãntu, sãmtu, Romanian sânt, Sardinian santu
Italic
Oscan saahtúm "sanctified," Umbrian sanśie, name of the god of trust
Celtic
Celtiberian sankilistara "money-fine"
Basque
Low Navarrese saindu "saint," "holy," Zuberoan sáintü 'id.,' borrowed from Spanish
sargento m. (Noun) "sergeant;" (f.) "battleaxe"
Old Spanish sargente. Borrowed from Old French sergent, from Medieval Latin servientem "servant," originally the accusative of serviens "serving," from the verb servire "to serve" (see servir).
The use of sargenta to indicate "battleaxe" derives from an old custom to refer to the feminine form of typically male professions in insulting overtones.
Indo-European
Romance
Portuguese servente, Catalan servent, French sergent, Italian serviente
se (1) (Pronoun) "oneself"
From Latin se 'id.' From Proto-Italic *se 'id.' From Proto-Indo-European *se 'id.'
In Proto-Indo-European, *s(u̯)e- meant "peculiar to oneself." Derivations from *su̯e- thus connote distinctiveness from other things. Benveniste (1973) writes, "This duality survived, as is revealed by the etymology, in the two forms se of Latin, which have become independent; the reflexive se, indicating “self,” and the separative se-, sed ‘but’, marking distinction and opposition."
se- (1), sed- Partitive prefix. "itself"
From Latin se(d)- 'id.' From se "oneself" (see se (1)).
se (2) (Pronoun) "him," "her," "them"
Old Spanish gelo. From Vulgar Latin gelo 'id.,' from Latin illi "to him." According to Roberts (2014), Old Spanish g- to Modern Spanish s- under influence from se (1).
se- (2) Prefix. "away"
From Latin se- 'id.' From Proto-Italic *sed "by itself." The ablative of se "itself" (see se (1), se (2)).
sección f. (Noun) "section"
From Latin sectionem, accusative of sectio 'id.' From secare "to cut." From Proto-Italic *seka-je/o- 'id.' From Proto-Indo-European *sekh1-i̯e/o- "to cut." Probably borrowed from another language.
Indo-European
Romance
Portuguese secção / seção, French section, Italian sezione
Balto-Slavic
Old Church Slavonic sěšti "to cut," Russian seč' 'id.,' Czech síci "to mow," Polish siec "to beat," Slovene sẹ́či "to cut"
Afro-Asiatic
Semitic
Ancient Hebrew śakkīn "slaughtering knife," Aramaic sakkīn 'id.,' in all likelihood, both Hebrew and Aramaic terms were probably borrowed
secreto (Adjective) "secreto"
13th cent. From Latin secretus 'id.,' passive participle of secernere "to separate," from se- "itself" and cernere "to discern" (see cerner).
Indo-European
Romance
Asturian secretu, Portuguese secreto, Galician secreto, Catalan secret, French secret, Italian secreto, Romanian secret, Sardinian segretu
seguir (Verb) "to continue," "to follow"
11th cent. From Vulgar Latin sequere, from Latin sequi 'id.' From Proto-Italic *sekw-e/o- 'id.' From Proto-Indo-European *sekw-e/o- 'id.'
Indo-European
Romance
Portuguese seguir, Catalan seguir, French suivre, suite, Italian seguire
Germanic
Old Irish sechithir "to follow," Germanic Gothic saiƕan "to see," Old Norse sjá 'id.,' Old High German sehan "to see," Old Saxon sehan 'id.,' English to see
Balto-Slavic
Lithuanian sèkti "to follow," Latvian sekt 'id.'
Hellenic
Ancient Greek ἕπομαι (hépomai) "to follow"
Indo-Iranian
Sanskrit sácate "to follow," Avestan haca- "to accompany"