dangerous */*/*/

UK [ˈdeɪndʒərəs] / US adjective

1) likely to harm or kill someone, or to damage or destroy something

a dangerous dog

a dangerous stretch of road

Air pollution has reached dangerous levels in some cities.

highly dangerous:

an exciting but highly dangerous sport

potentially dangerous:

Children are taught to avoid potentially dangerous situations.

dangerous to:

It is not yet known whether these chemicals are dangerous to humans.

it is dangerous (for someone) to do something:

It's dangerous to walk around here on your own at night.

2) likely to have a bad effect or to cause a problem

Mr Ashley is playing a dangerous game, pretending to support both parties.

it is dangerous (for someone) to do something:

It is extremely dangerous for you to get involved in this.

a dangerous precedent (= a decision that others will follow and that will cause problems):

The sacking of Mr Nolan could set a dangerous precedent.