What is the difference between ithm, maʿṣiya, khaṭīʾa, dhanb, wizr, sayyiʾa, and fāḥisha?

A "sin" (dhanb) is more general than an "offense" (ithm). A "sin" includes a transgression committed intentionally or unintentionally, unlike an "offense" which is always intentional. As for "burden/guilt" (wizr) and "offense" (ithm), they are descriptive. "Wizr" denotes strength (like "izar" - loincloth, or "wazir" - minister), while "ithm" implies pleasure. "Disobedience" (ma'siyah) and "sin" (dhanb) are synonyms, both being names for intentionally committing a forbidden act. "Error/fault" (khati'ah) is equivalent to "offense" (ithm) if committed intentionally. A "misdeed" (sayyi'ah) is that which results in sin and punishment. "Immorality/lewdness" (fahishah) refers to grave words and deeds, and is used euphemistically for fornication, as in the Almighty's saying: "And those who commit immorality (fahishah) among your women."