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sumo (1) (Adjective) "supreme"
10th cent. Old Spanish somo "highest," which is preserved in the archaic phrase en somo "in total." From Latin summus "highest." From Proto-Italic *sup(a)mo-'id.' From Proto-Indo-European *(h1)up-m̥(H)o- 'id.'
Indo-European
Romance
Portuguese sumo, Italian sommo
Italic
Umbrian sume "highest (place)"
Germanic
Gothic auhuma "highest," Old English yfemest 'id.'
Indo-Iranian
Sanskrit upama "uppermost"