mess with

phrasal verb

messed with; messing with; messes with

informal

1

: to cause trouble for (someone) : to deal with (someone) in a way that may cause anger or violence

I wouldn't want to mess with him.

You'd better not be messing with me.

2

chiefly US : to deal with or be involved with (something that causes or that could cause trouble)

The company doesn't want to mess with small distributors.

He doesn't want to mess with cocaine anymore.

3

: to handle or play with (something) in a careless way : to mess around with (something)

Don't mess with the camera.

Examples of mess with in a Sentence

Recent Examples on the Web

But the general consensus is that the chemical messes with insects’ senses of smell to keep them from biting, Jamie Kopco, PhD, a pesticide education specialist with the Penn State University Extension and a medical entomologist in the U.S. Army Reserve, told Health. —Jamie Ducharme, Health, 24 July 2025

When the researchers introduced a slight delay in the video feed, effectively messing with the volunteers’ predictions of where their hands should be, their perception of muscle fatigue increased. —Alex Hutchinson, Outside Online, 23 July 2025

Perhaps too many early years of watching Friday the 13th and Nightmare on Elm Street movies, with its heroes getting picked off one by one, has epigenetically messed with our brains and infused a feeling of grim inevitability. —Steven Zeitchik, HollywoodReporter, 23 July 2025

The last thing anyone wanted was to mess with the king. —Rustin Dodd, New York Times, 23 July 2025