Sick verse is a pejorative label for poetry that dwells on illness, decay, death, or other morbid subjects, often in a way the speaker sees as excessive or unhealthy. The phrase is not a neutral technical term; it usually signals criticism rather than a formal category of poem.
Because the expression is informal and can be used loosely, it may also be applied to poems with a deliberately bleak, gothic, or macabre tone.
Example
The moon was a bruise on the hospital wall,
The roses in the vase were already dust,
And every clock in the corridor
ticked like a bone.