(comparative more attern, superlative most attern)
- (UK dialectal) Venomous; poisonous.
- (UK dialectal, of people) Cruel; fierce; ill-natured.
From Middle English attern, from Old English ǣtren (“poisoned, poisonous, venomous”), from Proto-Germanic *aitrinaz (“poisonous”), equivalent to atter + -en. Cognate with Middle High German eiterin (“poisonous”). More at atter.