When the speaker in William sonnet 55 mentions this powerful rhyme he is referring to?

The speaker in William Shakespeare's Sonnet 55 is referring to the power of poetry itself when he mentions "this powerful rhyme."

Here's why:

* "Not marble, nor the gilded monuments / Of princes, shall outlive this powerful rhyme": This line establishes a contrast between physical monuments (marble, gilded statues) and the power of poetry.

* "But you shall shine more bright in these contents / Than unswept stone, besmeared with sluttish time": The speaker argues that poetry will preserve the subject's beauty and memory more effectively than physical structures that are subject to decay.

* "When wasteful war shall statues overturn, / And broils root out the work of masonry": He imagines a future where even the grandest monuments are destroyed, emphasizing the enduring nature of poetry.

Therefore, the "powerful rhyme" represents the enduring power of poetry to preserve memory and transcend time.