The Factors Leading to Enlightenment - 3 degrees of defilements

Defilements can be classified according to different degrees; they can be subtle, medium or coarse defilements. 
The coarse defilements, vítikkama kilesas are the defilements that are the condition for committing akusala kamma through the body or through speech. One can abstain from vítikkama kilesa by the observance of síla.
The medium defilements, pariyutthana kilesas arise with the akusala citta that is not of the degree of akusala kamma. They can be temporarily subdued by kusala jhanacitta, and that is elimination by suppression, (vikkhambhana pahana).
The subtle defilements are the inherent tendencies, anusaya kilesas. So long as defilements have not been completely eradicated the anusaya kilesas lie dormant in the cittas that arise and fall away in succession. They are like germs that condition the arising of the medium defilements.  Defilements cannot arise again when they have been completely eradicated (samuccheda pahana). When the lokuttara magga-citta realises the Noble Truths and experiences nibbana, anusaya kilesas are eradicated in accordance with the stage of enlightenment that has been attained. They are successively eradicated at the different stages of enlightenment.

Topic 237