Adverse (adjective)

1. Having a harmful effect or influence.
2. Opposing or blocking progress.
3. Difficult or unfavorable.

Origin:

Late middle english: from old french avers, from latin adversus "turned towards, opposed", past participle of advertere, from ad- "to" + vertere "to turn".

Examples:

1. The company faced many adverse conditions in the market.
2. The weather was adverse for sailing.
3. His health has been affected by the adverse effects of the drugs.
4. The adverse reaction of the public was unexpected.
5. The government has been slow in dealing with adverse economic conditions.