Refers to a barred enclosure for animals or a prison cell. The context usually makes the specific meaning clear.
The zoo's tiger is in a large cage.
彼は檻に入れられた。
He was put in a jail cell.
The keeper put the lion in the cage.
The monkey got out of its cage and ran off.
The prisoner was locked up in the cell.
The bear broke out of its cage and fled into the forest.