lake lettuce
n.— «Some might refer to them as moss, pond scum or lake lettuce, which encompasses a wide array of aquatic growth.» —“Weed control curtails two fishing trips” by Steve Ford Courier & Press (Evansville, Illinois) May 4, 2008. (source: Double-Tongued Dictionary)
Further reading
Why is boxing called the sweet science when it’s obviously such a bruising sport? Also, a mother of five is baffled when her Gen Z kids use words she thought she knew. For example, they call sweatshirts sweaters, and declare that’s so aesthetic...
Cat hair may be something you brush off, but cat hair is also a slang term that means “money.” In the same way, cat beer isn’t alcoholic — some people use cat beer as a joking term for “milk.” And imagine walking on a beach with a long stretch of...