It is that which has been concocted and fabricated.
It is known to be fabricated by one of four indications: (1) the confession of its fabricator; (2) something that takes the place of his confession;1 (3) circumstantial evidence concerning the state of the narrator;2 or (4) circumstantial evidence concerning the report itself.3
Ibn Daqīq al-ʿĪd said: "The narrator's confession of fabrication is sufficient to reject the report; but it is not decisive in establishing that the report is fabricated, since he may himself be lying in that very confession."
Al-Sakhāwī said: "He means it is not, in such a case, designated mawḍūʿ."
Al-Ḥāfiẓ said: "He means it is fabricated; but by predominant supposition, not by certainty."
It is not lawful for anyone who knows the condition of such a ḥadīth to narrate it without making clear that it is fabricated.4
Al-Ḥāfiẓ said: the more apt example here is that which al-Bayhaqī narrated in al-Madkhal with a sound chain: that they had disagreed, in the presence of Aḥmad ibn ʿAbd Allāh al-Juwaybārī, on whether al-Ḥasan had heard from Abū Hurayra; whereupon he narrated a ḥadīth to them, with his isnād to the Prophet ﷺ: "al-Ḥasan heard from Abū Hurayra." al-Nukat, p. 359. ↩
Al-Ḥāfiẓ said: the more apt example here is when a muḥaddith narrates from a teacher, and then mentions that his own birth-date falls after the date of that teacher's death. al-Nukat, p. 359. ↩
This is the most common case: that the matn is feeble in meaning, or contradicts the explicit text of the Book, the mutawātir Sunna, the certain consensus, plain reason, sense or witnessed observation, and so on. See: al-Iqtirāḥ, p. 228; Nukat Ibn Ḥajar, p. 361. ↩
Muqaddimat Ibn al-Ṣalāḥ, pp. 77–78; al-Iqtirāḥ, p. 229; Sharḥ al-Nukhba, pp. 56–57; Fatḥ al-Mughīth, 2/130. ↩
Ṣaḥīḥ and ḥasan are accepted in every case; ḍaʿīf is not accepted except in faḍāʾil and targhīb / tarhīb. Ibn Ḥajar's three conditions for accepting a weak ḥadīth in faḍāʾil.
Al-shādhdh is that which a single narrator has transmitted alone, raising doubt in the mind of the critic; this is also the definition of al-munkar. Statements of the early imāms show the two are one.
A ḥadīth in which a narrator has been replaced with another, whether one narrator, several, or even the entire chain, is al-maqlūb (literally, that which has been inverted).
Among the muḥaddithūn, al-majhūl is a narrator whose condition is not known and who is not known for his pursuit of knowledge; he splits into majhūl al-ḥāl (al-mastūr) and majhūl al-ʿayn.
