What is the meaning of Inequality?

Absence of equality.

A condition or state (of social, cultural, or legal matters) that is not equal; especially, such a condition that is thereby also unfair.

A statement that of two quantities one is specifically less than (or greater than) another. Symbol: ${\displaystyle <}$ or ${\displaystyle \leq }$ or ${\displaystyle >}$ or ${\displaystyle \geq }$ or ${\displaystyle \neq }$, as appropriate.

Unevenness, irregularity.

Source: wiktionary.org