sense of justice; feeling of righteousness; moral sense
Refers to a person's inner drive to do what is right or fair, often used when someone acts on principle or is moved by injustice.
He has a strong sense of justice, so he can't overlook wrongdoing.
Voices of protest arose against the verdict out of a sense of justice.
道徳心 is a broader moral sense or conscience, often related to general ethics, whereas 正義感 specifically focuses on fairness and justice.
Compound of 正義 (justice) + 感 (feeling, sense). The word is a straightforward Sino-Japanese formation.