Zulm is the Arabic

Arabic language

Arabic is a name applied to the descendants of the Classical Arabic language of the 6th century AD, used most prominently in the Quran, the Islamic Holy Book...

 word used interchangablely for cruelty

Cruelty

Cruelty can be described as indifference to suffering, and even positive pleasure in inflicting it. If this is supported by a legal or social framework, then receives the name of perversion. Sadism can also be related to this form of action or concept....

 or unjust acts of exploitation

Exploitation

This article discusses the term exploitation in the meaning of using something in an unjust or cruel manner.- As unjust benefit :In political economy, economics, and sociology, exploitation involves a persistent social relationship in which certain persons are being mistreated or unfairly used for...

, oppression, and wrong doing, whereby a person either deprives others of their rights or does not fulfill his obligations towards them.

People who commit zulm are called zalim-een.

In the Islamic context injustice or acts of cruelty are attributed to human acts and not to Allah

Allah

Allah is a word for God used in the context of Islam. In Arabic, the word means simply "God". It is used primarily by Muslims and Bahá'ís, and often, albeit not exclusively, used by Arabic-speaking Eastern Catholic Christians, Maltese Roman Catholics, Eastern Orthodox Christians, Mizrahi Jews and...

: God does not do injustice to anyone. It is the people who do injustice to themselves.