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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."
Indo-European
Romance
Catalan taca, Occitan taca, Italian tacca
Germanic
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)
Hellenic
Ancient Greek δεικνῠ́ναι (deiknynai) "to point out"
Indo-Iranian
Sanskrit diś "to point out"