Pariññā: 'full understanding', full comprehension. There are 3 kinds of mundane f.u. lokiya-p namely: full understanding of the known ñāta-p f.u. as investigating tīrana-p and f.u. as overcoming pahāna-p In Vis.M XX, 3 it is said:
Full understanding of the known is the knowledge consisting in the discernment of the specific characteristics of such and such phenomena, as: 'Materiality has the characteristic of being oppressed; feeling has the characteristic of being felt, etc.'
Full understanding by investigating is that insight-understanding vipassanā-paññā; see: vipassanā which has the 3 general characteristics impermanence, suffering, no-self as its objects, and which arises when attributing a general characteristic to physical and mental phenomena, as for instance: 'Materiality is impermanent, feeling is impermanent, etc.'
Full understanding by overcorning is that insight-understanding which has the above mentioned general characteristics as its objects, and arises after overcoming the idea of permanence, etc.
Maha Thera Nyanatiloka. Manual of Buddhist Terms and Doctrines, Buddhist Publication Society, first edition 1952.