Sub-commentaries (Theravāda)
The sub-commentaries (Pali: ṭīkā) are primarily commentaries on the commentaries (Pali: aṭṭhakathā) on the Pali Canon of Theravada Buddhism, written in Sri Lanka. This literature continues the commentaries' development of the traditional interpretation of the scriptures.
Source: Wikipedia — Sub-commentaries (Theravāda) (CC BY-SA 4.0)