big, considerable, enormous, grave, great, high, huge, major, serious, significant, substantial, terrible, tremendous
high-risk patients
a major risk to livestock

good
bad, poor
low, minimal, slight, small
added, additional, elevated, extra, heightened, increased, increasing
decreased, reduced
genuine, real
attendant, inherent, possible, potential
Standards of hygiene have fallen, with all the attendant risks of disease.
There are considerable risks inherent in the policy.

long-term, short-term
lifetime
overall
personal
They do their patriotic duty at great personal risk.

political
They run great political risks by opposing him.

relative
perceived
The perceived risk is far greater than reality.

unacceptable, unnecessary, unreasonable
acceptable, moderate
its judgment of what constitutes an acceptable risk

calculated
I take calculated risks but never gamble.

commercial, credit, environmental, financial, fire, health, insurance, safety, security
Those old boxes in the corridor are a fire risk.
He's a good insurance risk.

cancer, cardiovascular, disease, heart-disease, HIV, mortality, stroke
suicide
He is not a current suicide risk.

flight (esp. AmE)
His lawyer argued that he was not a flight risk (= that he would not try to run away, leave the country, etc.).

degree, level
element
The operation carries an element of risk.

face, run, take
If you don't study, you run the risk of failing.
I'm not prepared to take risks—I want the equipment thoroughly checked.

carry, create, entail, incur, involve, pose, present
Pollutants in the river pose a real risk to the fish.

heighten, increase, raise
double
Smoking doubles the risk of having a stroke.

cut, decrease, diminish, lessen, limit, lower, minimize, mitigate, reduce
Companies can mitigate the risks of losing valuable data.

avoid, eliminate
assess, calculate, determine, evaluate, measure, weigh, weigh up (BrE)
The directors will have to assess our credit risk.
You have to weigh risks and benefits.

know, understand
I think you know the risks of your choices.

identify
They try to identify every possible risk.

indicate
estimate, predict
manage
Farmers invest in irrigation to manage risk in drought years.

address
solutions to address security risks more effectively

accept, assume, bear
The lawyers are assuming all the financial risk.

spread
These funds spread the risk among different countries.

outweigh
The benefits outweigh the risks.

justify
The rewards may well justify the risks.

be considered
He is no longer considered a security risk in the State of California.

outweigh sth

group
Miners are a high risk group for certain types of gastric cancer.

factor
Cigarette smoking is a risk factor for this disease.

assessment
analysis
level
investors' assessments of overall risk levels

category
Young male drivers are a higher risk category compared to mature ladies and even women of the same age.

mitigation (esp. AmE), reduction
management
manager
aversion, avoidance
the strategies of risk avoidance that people practice in their everyday lives

tolerance
Consider your own risk tolerance. How many chances are you willing to take?

behaviour/behavior (esp. AmE)
efforts to persuade the public to reduce risk behavior

premium
a big jump in the risk premium on corporate bonds

at risk
to put someone's life at risk

at risk from, at risk of
Journalists in the zone are at serious risk of being kidnapped.

at risk for (esp. AmE)
Children are at greater risk for these diseases.

at the risk of
At the risk of sounding rude, don't you think you'd better change for the party?

at risk to
He saved the child at considerable risk to himself.

risk by
He knew he was taking a big risk by going skiing.

risk for (esp. AmE)
a reduced risk for heart disease

risk from
a risk from contaminated water

risk in
I was taking a big risk in lending her the money.

risk of
a higher risk of stomach cancer

risk to
a risk to health

at your own risk
The building is unsafe—enter at your own risk.

an increase in risk, a reduction in risk
risks and benefits, risks and rewards
the risks and benefits of a drug

cannot, dare not, not want to, would not
I simply can't risk being seen there.
I didn't want to risk being late.

be prepared to, be willing to
He was prepared to risk everything in order to achieve his ambition.

choose to, decide to
refuse to
I refuse to risk being hurt.

for
I am not risking my neck for anyone!

on
I wouldn't risk my money on this investment.

risk it
I knew I would be in trouble if I was found out, but I decided to risk it anyway.

risk life and limb
the brave tourist who risks life and limb for adventure

risk losing sth
families who risk losing their homes

Risk is used with these nouns as the object:
backlash, career, chance, confrontation, death, dismissal, embarrassment, fine, friendship, health, injury, life, neck, penalty, possibility, prosecution, rejection, reputation, ridicule, safety, wrath