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tesoro m. (Noun) "treasure"

Of unknown origin, borrowed from a non-Indo-European language. From late Proto-Indo-European *dhí-dheh1- 'id.,' reduplication of the Proto-Indo-European root *dheh1- "to put."

Romance: Western Vulgar Latin: Portuguese tesouro, Catalan tesaurus, French trésor, Italian tesauro ; Eastern Vulgar Latin: Romanian tezaur
testigo (Noun) "witness"

12th cent. From Old Spanish testiguar "to testify," having now become atestiguar.

Romance: Western Vulgar Latin: Portuguese testificar, Italian testificare
tiempo m. (Noun) "time;" "weather"

12th cent. From Latin tempus 'id.' From Proto-Italic *tempos- "stretch." From Proto-Indo-European *temp-os- 'id.,' from the verbal root *temp- "to stretch."

Romance: Western Vulgar Latin: Asturian tiempu, Portuguese tempo, Galician tempo, Catalan temps, French temps, Italian tempo ; Eastern Vulgar Latin: Romanian timp ; Sardinian: tempus

Italic: Latin templum "shrine"

Indo-European: Germanic: Old Norse þǫmb "bow-string;" Balto-Slavic: BCS tetíva "bow-string," Old Prussian tēmpran "expensive," Lithuanian tem̃pti "to pull" Tocharian: A cämpäṣ "is able," B campäṃ "to be able"
tienda f. (Noun) "store;" "tent"

10th cent. Borrowed from Medieval Latin tenda "tent." Originally referring to cloth stretched between stakes. From Latin tendere "to stretch" (see tender).
tierra f. (Noun) "earth;" "dirt;" "land"

10th cent. From Latin terra 'id.' From Proto-Italic *tersa- 'id.' From Proto-Indo-European *ters-h2- "dry land," from the verbal root *ters- "to dry out."

Romance: Western Vulgar Latin: Asturian tierra, Portuguese terra, Galician terra, Catalan terra, French terre, Italian terra ; Eastern Vulgar Latin: Aromanian tsarã, Romanian țară ; Sardinian: terra

Italic: Oscan teras "of the earth"

Indo-European: Celtic: Old Irish tír "territory," "dry," Old Welsh tir 'id.,' Middle Breton tir 'id.,' Old Cornish tir 'id.;' Anatolian: Hittite tars- "to become dry"
tío (Noun) (m.) "uncle;" (f.) "aunt"

10th cent. From Late Latin thius 'id.,' borrowed from Ancient Greek θεῖος ‎(theîos) 'id.' Of unknown origin.

Romance: Western Vulgar Latin: Asturian tíu, Portuguese tio, Catalan tio, Italianzio ; Sardinian: tiu
tipo m. (Noun) "type"

Early 17th cent. From Late Latin typus "image," borrowed from Ancient Greek τύπος ‎(typos) “mark." From the verb τύπτειν (typtein) "to poke." From Proto-Indo-European *(s)teu̯p- "to beat," "to push" (see estupido).

Indo-European: Albanian: shtyp "to crush"
tirar (Verb) "to throw"

12th cent. From Vulgar Latin *tirare 'id.' Of unknown origin.

Romance: Western Vulgar Latin: Portuguese tirar, Catalan tirar, French tirer
tiro m. (Noun) "throw"

Late 15th cent. From tirar.
ti, tí (Pronoun) "to you"

From Vulgar Latin ti 'id.,' from Latin tibi 'id.' From Proto-Italic *tefei, from Proto-Indo-European *tébhi̯o 'id.,' with an enclitic form *toi.

Romance: Western Vulgar Latin: Portuguese ti, Romanian ție

The extension of *-i to *-ei (*tébhi > *tebhei) was due to analogy with other dative nouns. This occurred in Balto-Slavic as well, but not in other language branches (Sihler 2008).