Ingratitude

[Sarah]

Want of gratitude; insensibility to, forgetfulness of, or illreturn for, kindness or favors received; unthankfulness;ungratefulness.Ingratitude, thou marble-hearted fiend. Shak.Ingratitude is abhorred both by God and man. L'Estrange.

[Cami]

A discreditable [lack] of [gratitude].

[Renato]

[Ingratitude] is thinking nothing of what has been done or given to you by someone else. That is to say, not feeling [bound] to show [gratitude]. In other words, [ingratitude] is a discreditable lack of gratitude. In fact, it is simply lack of appreciations or thanks for something given or done to you or to someone else. -Emeasoba George

[Jason Yan]

the fact that someone is not grateful for something