What is the meaning of tombs do worms from William Merchant

The phrase "Tombs do worms from William Merchant" is a line from the poem "The Mad Maid's Song" by William Shakespeare. In the poem, Ophelia, a young woman driven mad by her lover Hamlet's rejection of her, sings a nonsensical song that contains this phrase. The phrase itself has no literal meaning, but it is thought to be a reference to the fact that even in the most opulent and expensive tomb, one will ultimately be consumed by worms. This is a reminder of the transience of life and the inevitability of death, even for those who seem to be the most powerful and privileged.