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enemigo m. (Noun, Adverb) "enemy," "hostile"
12th cent. From Latin inimicus 'id.' From in- "not" and amicus "friend" (see in- and amigo respectively).
Indo-European
Romance
Asturian enemigu, Portuguese inimigo, Catalan enemic, French ennemi, Italian nemico, Romanian inamic, Sardinian anemigu
Celtic
Old Irish námae "enemy," from *n̥-h2mh3- "one not taken hold of," "non-friend"