The act of a person (mostly lolis) going beyond the normal level of lewd; for example the transition from ecchi to hentai.
Girl: Big brother in your absence I begun to unlock the full potential of my loli powers.

Boy: Excellent you have just experienced a 'lewdening'. with every loli you destroy your lewdness shall grow. Come we must go somewhere to continue your training. We must make you lewder

Girl: I love you big brother.

Boy: As I you!

*Police sirens*
by tfwntai August 15, 2017
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