an allegation that something imposes an illegal obligation or denies some legal right or causes injustice(noun.communication)
source: wordnet30
a complaint about a (real or imaginary) wrong that causes resentment and is grounds for action(noun.communication)
source: wordnet30
A cause of uneasiness and complaint; a wrong done and suffered; that which gives ground for remonstrance or resistance, as arising from injustice, tyranny, etc.; injury.(noun)