shameless
adj.adj. showing no feeling of guilt or embarrassment about doing something bad. You use this when someone acts in a way that should make them feel bad, but they don't care.
adj. showing a lack of shame or guilt, especially regarding conduct that is socially or morally unacceptable. Often carries a strong pejorative tone when describing public behavior or self-promotion.
He told a shameless lie to get out of trouble.
The politician made a shameless attempt to win votes by making promises he knew he could not keep.
Despite the evidence against him, he maintained a shameless disregard for the truth, continuing to profit from the very scheme that had ruined his reputation.
From Middle English shameles, shamelees, schameles, schomeles, schomeleas, from Old English sċamlēas, sċeamlēas (“without shame; shameless”), from Proto-Germanic *skamalausaz (“shameless”), equivalent to shame + -less. Cognate with West Frisian skamteleas (“shameless”), Dutch schaamteloos (“shameless”), German schamlos (“shameless”), Danish skamløs (“shameless”), Swedish skamlös (“shameless”), Icelandic skammlaus (“shameless; unashamed”).
Typically used attributively before a noun to criticize a person's actions or character.