Definition of frass
: debris or excrement produced by insects
Recent Examples of frass from the Web
Look for the dark frass (or bug poop) on leaves, then spray water on the plant in that general vicinity.
As the insects grow, the Beta Hatch team removes the frass the mealworms produce, and replenishes their food.
Beta Hatch now has a grant in partnership with those scientists to find out if the bugs can still be consumed by livestock, and if the frass will still be safe for plants if they are fed an all-plastic diet.
The frass contains a particular type of microbe that enables the larvae to digest the cow dung into which they was born.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'frass.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
Learn More about frass
Seen and Heard
What made you want to look up frass? Please tell us where you read or heard it (including the quote, if possible).