Is this your crossword clue?
"duty" is also used as a crossword clue. If that's what you saw, the answer is often obligation (10 letters).
Definitions
work that you are obliged to perform for moral or legal reasons
Word origin
From Middle English duete, from Middle English dewe + Middle English -te. Equivalent to due + -ty.
Used in a sentence
“Do your duty by me! -No, we don't have a duty to keep you abreast.”
“1805, 21 October, Horatio Nelson England expects that every man will do his duty.”
“Your Excellency, I trust you will not find it necessary to use that word again. Were I not completely aware of my duty to my family and to my country, I would not have come back tonight…or indeed ever again!”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer2 curated clues
01“Required task”4 letters
02“Obligation”4 letters
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