One document from around 1300 describes the Botafumeiro as "now part of the ceremony" [3].
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In Galician, "botar" means "to eject, to throw away, to expel", from Occitan, and "fume" means "smoke", from Latin[1].
The claim that the Botafumeiro is the largest thurible in the world is often made, but in fact there is a thurible in Lohne, Oldenburg, Germany that reportedly weighs 500 kg and stands 3.21 meters high [2].