Lacking care or attention to duty; negligent in performing obligations.
From Latin 'remissus' meaning 'relaxed, loose', past participle of 'remittere' meaning 'to send back or slacken'. The sense of being negligent developed from the idea of being slack or loose in one's duties.
Remiss carries a moral weight that 'forgetful' lacks - it implies not just oversight but a failure of character or responsibility. The word often appears in formal apologies ('I would be remiss if I didn't thank...'), showing how we use elevated language to acknowledge our shortcomings.
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