IPA: /ˈʃeɪmləs/
KK: /ˈʃeɪmləs/
Not feeling or showing any shame; behaving in a way that is considered wrong or inappropriate without feeling embarrassed.
He made a shameless attempt to take credit for someone else's work.
Shameless → It is formed from "shame" (from Old English "sceamu", meaning a feeling of guilt or disgrace) and "-less" (meaning without). The word "shameless" describes a state of being without shame or guilt.
Think of being 'without' ('-less') a feeling of 'guilt' ('shame') — that's why shameless means lacking shame.