Answer: It is slackening in performing acts of goodness and in carrying out one's duties.

It includes slackness in carrying out obligations.

Allah Almighty says: {The hypocrites seek to deceive Allah, but it is He Who deceives them. Whenever they stand up for prayer, they stand up reluctantly, only to be seen by people, and they do not remember Allah but a little.} [Surat an-Nisā’: 142]

The believer should, thus, abandon indolence, sluggishness, and laziness and should work hard and work diligently in this life in a way that is pleasing to Allah Almighty.