'perversions' or 'distortions'. -
''There are 4 perversions which may be either:
of perception (saññā-vipallāsa),
of consciousness (citta v.)
or of views (ditthi-v.).
And which are these four? To regard:
what is impermanent (anicca) as permanent;
what is painful (dukkha) as pleasant (or happiness-yielding);
what is without a self (anattā) as a self;
what is impure (ugly: asubha) as pure or beautiful''
(A.IV.49). - See Manual of Insight, by Ledi Sayadaw (WHEEL 31/32). p.5.
"Of the perversions, the following are eliminated by the 1st path-knowledge (sotāpatti): the perversions of perception, consciousness and views, that the impermanent is permanent and what is not a self is a self; further, the perversion of views that the painful is pleasant, and the impure is pure.
By the 3rd path-knowledge (anāgāmitā) are eliminated: the perversions of perception and consciousness that the impure is pure.
By the 4th path-knowledge (arahatta) are eliminated the perversions of perception and consciousness that the painful is pleasant" (Vis.M. XXII, 68).