Poison and disease absorptionEdit
It seems that spell absorption also functions as protection against poison 'spit' (Chaurus and spiders) and disease (most wild animals) as both of this have been seen triggering the spell absorption effect. This would seem to indicate this attacks are counted as magic by the game. Since having high (70%) spell absorption my character very rarely gets diseases, although they also have 50% disease resistance as well.
Further evidence comes from the Chaurus page which suggest their spit can be blocked by wards.
Weapons coated with poison and ingested poisons do not seem to trigger spell absorption.