couldn't carry a note in a bucket

An idiomatic American expression meaning someone sings very badly, so badly they could not manage to keep a melody contained even in something as solid as a bucket. A hyperbolic and colorful way to describe someone as tone-deaf or musically hopeless. Used in affectionate teasing as often as genuine criticism. The bucket image turns an abstract deficiency into a delightfully concrete absurdity.

(idiomatic, slang) Sings very badly.

An American idiomatic expression meaning someone is completely unable to sing — they are so tone-deaf or vocally inept that even the most charitable listener would struggle to call what they produce music. The humor lies in the absurdist image of carrying a tune like a physical object and still failing. Typically used in a teasing, affectionate, or blunt way to describe someone's singing without pulling punches. Common in everyday American speech and not considered offensive.