A supernova progenitor (SN progenitor) is a star or star system (or anything) that produces a supernova. They can be classified by the overall type of supernova.
The progenitor of a core collapse supernova (virtually any type supernova other than Type Ia, a core collapse supernova progenitor) is a massive massive post-main-sequence star within a range roughly of 25 to 40 or 50 solar masses during its main-sequence; it is thought that above this range, the core collapse will not cause a supernova explosion and even within the range, it is thought some may collapse without the explosion and the question of which circumstances lead to an explosive collapse is still an area of debate and study interest. Some such massive stars have exotic phases within their post main-sequence, such as Wolf-Rayet stars.
The progenitor of a Type Ia supernova (Type Ia supernova progenitor) is a white dwarf with a companion, either a star feeding it sufficient mass (mass transfer) to reach the Chandrasekhar mass (leading to a collapse that triggers fusion) or another white dwarf with which it collides: these two theories are known as the single degenerate model and the double degenerate model, and it is considered possible that both occur. In the former case, the notion that it occurs at a particular mass (the Chandrasekhar limit) suggests a straight-forward reason why they may be taken as standard candles, but the latter case makes such a theory less straight forward. The former case of accretion is also somewhat similar to the progenitor of a nova: which is fusion occurring on the surface of a white dwarf due to accretion. The circumstances leading to each is a topic of active research, including the notion that a nova can trigger a Type Ia supernova, possibly even if the White dwarf lacks the full Chandrasekhar mass (a sub-Chandrasekhar mass detonation).