adverse
ad·verse
/ædˈvɚs, ˈædˌvɚs/ adj [more ~; most ~]
: bad or unfavorable : not good
adverse criticism/remarks
He had an adverse reaction to the medicine. [=he reacted badly to the medicine; the medicine had a bad effect on him]
Many fear that budget cuts will have an adverse [=damaging] effect on education.
adverse circumstances/conditions/weather
The drug has no adverse [=harmful] side effects.
ad·verse·ly adv
Sales were adversely affected by the bad weather.
Staff changes could affect the project adversely.
