The Abhidhamma is the third basket of the canon. It analyses experience into ultimate elements, dhammas: moments of consciousness, mental factors, material phenomena and nirvāṇa, with their conditions. Its scholastic tradition, continued in commentaries, underlies the Visuddhimagga. The Sarvāstivāda had its own Abhidharma.
Abhidhamma
The “higher teaching”: the systematic Buddhist analysis of mind and matter into momentary elements.
Also: Abhidharma