What is the meaning of secularism in the Indian Constitution?

In the Indian Constitution, secularism means that the State has no official religion and treats all religions equally. It guarantees that every citizen has the freedom to profess, practice, and propagate any religion or choose not to follow any religion at all (Articles 25–28). 

The government cannot favor, promote, or discriminate against any religion in its policies or laws. This ensures equal respect for all faiths and protects the unity and integrity of the nation by preventing religious dominance in public affairs.