"Tadlīs": hiding, concealing. Other meanings: deception, cheating, betrayal, decrease.
"Tābi‘i": It is derived from "tābi‘", which means someone who follows and imitates another. Other meanings: successor, obedient, masterful.
A Hadith with different, yet equally strong, narrations, so these narrations cannot be reconciled or weighed against each other.
A Hadith that has two or more successive narrators dropped form its chain of narrators.
A Hadith that is narrated by a weak narrator, opposing thereby the narration of a reliable narrator.