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brezo (1) m. (Noun) "heather"
13th cent. Old Spanish bruezo. From Vulgar Latin *broccius 'id.,' from Proto-Celtic *wroiko- 'id.' Of unknown origin but probably borrowed from the same source language as the Balto-Slavic "heather"-words (infra).
Variants
Navarre beruezo, La Rioja brozo
Indo-European
Romance
Asturian berezu, gorbizu (< *go-brizu), (Palacios del Sil) bouza "thicket," Galician breixo, Old French bruiere
Celtic
Welsh grug "heather," Old Irish freoch "heather," Gaelic fraoch 'id.'
Balto-Slavic
Russian véres "heather," Slovene vrẹ̑s "heather," Polish vřes "heather," Lithuanian vìržis "heather," Latvian vir̂zis 'id.'