The only free and comprehensive online etymological dictionary of the Spanish language
tabla f. (Noun) "plank;" "slab"
12th cent. From Vulgar Latin tabla 'id.' From Latin tabula "board." From Proto-Italic *taflā- 'id.' Of uncertain origin.
Portuguese talião, Italian taglione
In the 3rd or 4th cent. text Appendix Probi we find the line: tabula non tabla "[the word for 'board' is] tabula, not tabla." The author's spelling correction proves how the word was pronounced by common speakers, and offers a rare glimpse of the evolution of Latin into Romance languages such as Spanish.
taca (1) f. (Noun) "small closet"
Very early 17th cent. Borrowed from Andalusian Arabic ṭáqa "window." From Arabic ṯāq 'id.,' which was borrowed from Persian ṭāq 'id.'
taca (2) f. (Noun) "stain"
12th cent. From Vulgar Latin *tacca 'id.' Borrowed from a Germanic language with the structure *taik(k)- "sign" (cf. Gothic taikns "omen"). Derived from Proto-Germanic *taikna- "sign." Perhaps from a Proto-Indo-European root *dei̯ḱ- meaning "to show."
Catalan taca, Occitan taca, Italian tacca
Gothic taikns "omen," Old Norse teikn "sign," Old High German zeihhan "sign," Old Dutch teikan 'id.,' Old Saxon tēken 'id.,' Old Frisian tēken 'id.,' Old English tācn 'id.' (English token)
Ancient Greek δεικνῠ́ναι (deiknynai) "to point out"
Sanskrit diś "to point out"
taca (3) f. (Noun) "crucible plate"
14th cent. Borrowed from French taque 'id.' According to Corominas (1991), taque was borrowed from Low German tak "cast iron plate," but no supporting sources found.
taca (4) f. (Noun) (Chile) "Bivalvia mollusk"
According to Actes (1901), from Mapuche thaca 'id.'
Chile cháca "Venus thaca shell," "labia minora," traca "Bivalvia mollusk"
tacaño (Adjective) "stingy"
14th cent. Old Spanish meaning "rogue." Of unknown origin. Popularly connect with Hebrew taqanah "agreement" (Corominas 1991). As Roberts (2014) explained, tacaño was "a word used in financial operations, and adopted by Christians in a pejor[ative] sense."

Romance scholars are more skeptical. "Corominas' philological survey of the spotty record of tacaño ... is as scrupulous as any exacting reader can demand.... But on the positive side he remains completely unconvincing. Between [Old Spanish] tacana 'payment' (whose stress pattern remains problematic), also [Judeo-Spanish] tacaná 'ruling, arrangement' flanked by the verb atacanar (Balkan peninsula), on the one hand, and, on the other Late [Old Spanish] tacaño 'rogue,' 'evildoer' there remains a triple gap: prosodic, semantic-stylistic, and morphological-derivational. If an original Orientalism is at all involved, it qualifies only as a very dubious one." ~ Malkiel, "Dubious, Pseudo-, Hybrid, and Mock-Orientalisms in Romance" (1991)
Italian taccagno
tajar (Verb) "to cut"
10th cent. From Latin taliare 'id.' From talea (botanical) "cutting" (see tálea).
Asturian tayar, Galician tallar, Portuguese talhar, Catalan tallar, French tailler, Italian tagliare, Romanian tăia, Sardinian tazare
Umbrian tafle "on the table"
tal (Adjective) "such"
10th cent. From Latin talis 'id.' From Proto-Italic *tāli- 'id.' From Proto-Indo-European *teh2-li̯- 'id.' from the demonstrative stem *teh2.
Portuguese tal, French tel, Italian tale, Romanian tare
Welsh talu "to pay," Middle Breton taluout "to be worthy," Cornish tal "to pay"
Old Church Slavonic tolь "so much," Lithuanian tõlei "until"
Ancient Greek τηλίκος (telíkos) "of such an age"
tálea f. (Noun) "Roman palisade"
From Latin talea "stick." Of unknown origin.
Italian talea
talento m. (Noun) "talent;" (money) "talent"
12th cent. From Medieval Latin talentum 'id.,' borrowed from Ancient Greek τάλαντον ‎(tálanton) "talent," "balance." From Proto Indo-European *tl̥h2-ent- "bearing." From the root *telh2- "to bear."
Portuguese talento, tento, Catalan talent, French talent, Italian talento