1‘the plane crashed into a lake in adverse weather conditions’
unfavourable, disadvantageous, inauspicious, unpropitious, unfortunate, unlucky, untimely, untoward
disagreeable, unpleasant, bad, poor, terrible, dreadful, dire, wretched, nasty, hostile
2‘the company knew of the drug's adverse side effects’
harmful, dangerous, injurious, detrimental, hurtful, deleterious, destructive, pernicious, disadvantageous, unfavourable, unfortunate, unhealthy
3‘the military feared an adverse response from the American public’
hostile, unfavourable, antagonistic, unfriendly, ill-disposed, negative, opposing, opposed, contrary, dissenting, inimical, antipathetic, at odds
We take a look at several popular, though confusing, punctuation marks.