open fire noun [C] (US open fireplace)
a space in a wall of a building in which wood or coal is burnt, and which has a chimney inside the wall to take the smoke away, or a fire which burns in such a space:
We roasted chestnuts on the open fire.

[TahlilGaran] Advanced Learner's Dictionary ▲

shoot verb [intransitive and transitive] to use a gun to fire bullets, or to kill or injure someone using a gun:
He ordered his men to stop shooting.
The guards shot the man as he was trying to escape.
President Kennedy was shot by a lone gunman.
fire verb [intransitive and transitive] to shoot bullets from a gun, or send an explosive object towards someone or something:
Soldiers fired into the crowd.
Helicopters fired rockets at several buildings.
He regained his balance, took aim, and fired.
The police fired into the air to make the crowd break up.
As soon as we crossed the border, enemy troops started firing at us.
Kendrick fired three shots at the President’s car.
Suddenly the car stopped, and the passenger got out and fired a Kalashnikov rifle at the police car.
launch verb [transitive] to send a large rocket or missile into the air:
American warships launched cruise missiles.
The guerrillas launched their rockets from densely populated towns.
open fire to start shooting:
Nineteen students were injured after a gunman opened fire.
Troops opened fire on a group of unarmed demonstrators.
The colonel gave the order for the soldiers to open fire.
shell verb [transitive] to fire shells (=metal containers filled with an explosive substance) at enemy soldiers, cities etc in a war, using large guns:
Border towns have been shelled by enemy aircraft for the past two months.
British warships began shelling German positions along the coast.
bombard verb [transitive] to attack a place for a long time with shells or bombs:
Allied forces bombarded the coast prior to the invasion.
Troops bombarded the area with shells.
The allied forces bombarded the enemy trenches for weeks.
Cromwell’s men had been bombarding the fort with their artillery for several days.
take a potshot at somebody/something to shoot at someone or something without aiming very carefully:
Someone tried to take a potshot at him, but hit the man behind instead.

[TahlilGaran] English Thesaurus ▲

open fire
open fire (on (someone/something))
to begin shooting at someone or something.
Do not open fire until you hear the command.

[TahlilGaran] English Idioms Dictionary ▲

open fire
v. phr. To begin shooting.
The big warship turned its guns toward the enemy ship and opened fire.
When the policeman called to the robber to stop, he turned and suddenly opened fire.

[TahlilGaran] English Idioms Dictionary ▲