Having lost courage, confidence, or hope; discouraged and without enthusiasm or determination.
From demoralise + -ed (past tense/adjective suffix). The British spelling retains the -ise form while American English uses -ize, but both produce the same adjective meaning state of lost morale.
A demoralised person is someone whose fighting spirit has been broken—they might be physically fine but mentally defeated. This is why prisoners and oppressed people so often seem to lose the fire to resist.
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