Average everydayness is a pre-ontological understanding. It is that mode of being whereby dasein is hardly a stranger to us.
Average everydayness is the only way of gaining insight into the features that belong to every Dasein.
Average everydayness is the enormous part of existence which is not spent reflexive contemplation, but in the involvement in tasks.
Average everydayness is that undifferentiated character of dasein, which is not nothing, but is actually a positive phenomenological characteristic of this entity... that is its averageness.
Average everydayness is not the usual hazy indefinite connotations that these words have in ordinary speech. In the explication of dasein, anything that is understood ontically can be thought of as existing in an average way and this mode may be grasped in patterns of existence.
Average everydayness is not to be taken as an aspect of dasein. Dasein comports itself towards its being in the mode of average everydayness, and the understanding of this is felt by dasein even before it can even be articulated in thought.