Causing loss of courage, confidence, or hope; discouraging and disheartening.
From demoralise + -ing (present participle/gerund suffix). The -ing form functions as an adjective describing things that have the effect of demoralising someone.
A demoralising event is one that spreads like a contagion—imagine a terrible defeat that makes everyone think 'what's the point?' The loss itself matters less than the psychological surrender it creates.
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