Al-gharīb is of two categories. There is a ḥadīth that is gharīb because it is narrated only through a single route, and there is a ḥadīth narrated through many routes that is still considered gharīb because of a particular isnād.
The first is al-fard al-muṭlaq (the absolute solitary); the second is al-fard al-nisbī (the relative solitary).1
Example of the absolute fard (al-fard al-muṭlaq): the ḥadīth of ʿAbd Allāh ibn Dīnār from Ibn ʿUmar, that the Prophet ﷺ prohibited the sale and gift of patronage. Al-Tirmidhī said: gharīb, not known except from the narration of ʿAbd Allāh ibn Dīnār. Example of the relative fard (al-fard al-nisbī): the ḥadīth of Burayd ibn ʿAbd Allāh ibn Abī Burda from his grandfather Abū Burda from Abū Mūsā from the Prophet ﷺ, who said: "The disbeliever eats in seven intestines, while the believer eats in a single intestine." Al-Tirmidhī said: this ḥadīth is gharīb from this aspect by way of its isnād, though it has been narrated through other routes from the Prophet ﷺ; only its narration through Abū Mūsā is regarded as gharīb. See: ʿIlal al-Tirmidhī al-Ṣaghīr, 2/238 (printed with the Indian edition of Sunan al-Tirmidhī). ↩
The rejected report falls into two kinds: that rejected because of an omission in the isnād, and that rejected because of criticism of the narrator.
A ḥadīth narrated through different but closely comparable routes that cannot be reconciled is al-muḍṭarib; iḍṭirāb renders it weak, as it implies an absence of ḍabṭ.
Al-mudraj is the mixing of what belongs to one speaker with what belongs to another without indication. It falls into mudraj al-matn (more common) and mudraj al-sanad.
Ḥadīth, in the muḥaddithūn's classification, is of two categories: al-mutawātir and khabar al-wāḥid.
