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"neglectful" is also used as a crossword clue. If that's what you saw, the answer is often remiss (6 letters).
Definitions
failing in what duty requires
Word origin
From neglect + -ful.
Used in a sentence
“Neglectful of her fine voice, she was obviously attending more to her companions than to her own singing;...”
“2005, Plato, Sophist. Translation by Lesley Brown. 243a-b, That they were too neglectful of ordinary people like us and overlooked us.”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer1 curated clues
01“Careless in duty”10 letters
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