Remiss (adjective)

1. Negligent in performing a duty or task.
2. Failing to take proper care or attention.

Origin:

The word remiss comes from the latin word remissus, meaning relaxed or slack.

Examples:

1. It would be remiss of me not to mention the work of my colleagues.
2. I was remiss in my duties as a manager.
3. It would be remiss to ignore the problem.
4. It would be remiss not to consider all the options.
5. The government was remiss in its response to the crisis.