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-oso Adjective-forming suffix indicating an abundance or a bundle.
From Latin -osus, Old Latin -osos. From Proto-Italic *ōnt-to- 'id.' From Proto-Indo-European *o-u̯ont-to- 'id.'
Indo-European
Romance
Asturian -osu, Portuguese -oso, Catalan -ós, French -eux, Italian -oso, Aromanian -os, Romanian -os, Sardinian -oso