An Injustice

1. Absence of justice; unjustice.
2. Violation of the rights of another person or people.
3. Unfairness; the state of not being fair or just.

Injustice and unjust use different prefixes, as French injustice was borrowed into English, while unjust was formed as un- + just. The spelling injust, from French injuste, is very rarely used, and unjustice, from un- + justice, is nonstandard.

justicelessness

unjustice (nonstandard)

wrong

wrength