The best replacement for duty is responsibility.

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Your alternative for duty is not listed? Suggest!
Speaking about duty, one probably shouldn't forget about right.

Other search terms related to duty and their ratings are:
★★★★★ right
★★★★★ gamepad
★★★ night vision goggles
You have in mind a companion for duty and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of duty in all years. Click on graph for more.
duty
responsibility
medal of honor