angry, strong, violent
non-violent, peaceful
sit-down (BrE)
mass
massive
formal, official
popular, public, student
anti-government, anti-war, etc.
political, social
continuing
rooftop (BrE), street
a rooftop protest by prison inmates
street protests by residents

widespread

storm, wave
The new tax sparked a wave of public protest.

organize, stage
lead
lodge, make, register
The Samoan team lodged a formal protest against the decision.
The government has made an official protest.

lead to, spark
ignore

group, movement
demonstration, march, meeting, rally
strike (esp. BrE)
petition (esp. BrE)
vote
song

in protest
Prisoners shouted and hurled slates in protest.

under protest
The strikers returned to work, but under protest.

without protest
The crowd dispersed without protest.

protest about
a protest about the new bypass

protest against
There had been a number of public protests against the new tax.

protest over
a student protest over tuition fees

a chorus of protest, a cry of protest, a howl of protest
The announcement brought cries of protest from the crowd.

a letter of protest
in protest at (esp. BrE), in protest of (AmE)
The party boycotted the election in protest at alleged vote rigging.
Winters quit the company board in protest of Eisner's plans.

strongly, vehemently, vigorously
formally
publicly
loudly
mildly
weakly
peacefully
the right to protest peacefully

angrily, bitterly, indignantly

begin to, try to
When he tried to protest, she insisted.

gather to
Crowds gathered to protest about the police violence.

about, over
Many people protested over the tax increase.

against
They were protesting against the proposed agreement.

at
Many people have protested at the cuts in state benefits.

to
We have protested to the government.

the freedom to protest, the right to protest
They were exercising their lawful right to protest.

Protest is used with these nouns as the subject:
demonstrator, muscle

Protest is used with these nouns as the object:
arrest, decision, injustice, innocence, movement, occupation