Untoward means unfortunate, unexpected, or inappropriate, usually describing something that causes problems or concern. When a school field trip goes smoothly with no untoward incidents, nothing bad or worrying happened: nobody got hurt, no one got lost, and everyone followed the rules.

The word often appears when people want to say that everything went fine, or that they hope nothing goes wrong. A parent might tell a babysitter to call if anything untoward happens, meaning any kind of trouble or emergency. A teacher reviewing classroom behavior might note that nothing untoward occurred during the substitute's visit.

Untoward can also describe behavior that's improper or unsuitable for the situation. If a student makes an untoward remark during a serious assembly, they've said something inappropriate for that moment. The word carries a slightly formal tone, like something an adult would write in a report rather than say casually to a friend. You're more likely to see it in books or hear it from teachers and parents than from kids talking on the playground.