Final answer:
The significance of the compass in 'A Valediction: Forbidding Mourning' is that it is a metaphor for love.
Step-by-step explanation:
In "A Valediction: Forbidding Mourning," the compass is a metaphor for love. The compass represents a couple's deep connection and unity, even when physically separated. Just as a compass's two legs are joined at the top, the souls of the lovers are connected despite being apart.