“problem”

A difficulty that has to be resolved or dealt with.

A child who is particularly difficult to raise or educate, especially due to a lack of self-control and disruptive and antisocial behavior.

To ponder, to go over in one's mind.

Of low quality.

Afterward in time (used with than when comparing with another time).

Operation; action.

An affair, condition, or subject, especially one of concern or (especially when preceded by the) one that is problematic.

The process of developing; growth, directed change.

Something that is representative of all such things in a group.

A response or reply; something said or done in reaction to a statement or question.

A person who calls attention to or complains about a flatus is likely trying to pretend it wasn't their own.

To make a mess of; to untidy, disorder, soil, or muss.

To bypass or circumvent (a problem or obstacle).