Someone who is feckless is incompetent and lacks the determination or skill to achieve much of anything at all in life.
When you are listless, you lack energy and interest and are unwilling to exert any effort.
A hapless person is unlucky, so much so that a stream of unfortunate things has happened and continues to happen to them.
When someone speaks in an artless fashion, they are without deception; when someone acts artlessly, they are being totally natural.
A fruitless effort at doing something does not bring about a successful result; rather, it has been time spent pointlessly.
A ruthless person shows no pity or mercy to an opponent.
If you do something that is senseless, there is no purpose or good reason for doing it; the thing that's done is often harmful or stupid in some way as well.
If someone does something that is pointless, there is no reason behind or meaning for doing it.
free of guilt
lacking protection or support
requiring or apparently requiring no effort
without a basis in reason or fact
deprived of life
having or showing no mercy
having no living or known mother
eminent beyond or above comparison
without mercy or pity
having little or no weight or apparent gravitational pull
(of especially persons) lacking sense or understanding or judgment
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