A metaphor is a figure of speech that compares two things that are unrelated but may share common characteristics. In the poem "The Silken Tent," Robert Frost extends his one central metaphor throughout the entire poem. In it, he compares a woman to a silken tent at noon as it waves gently in a summer breeze. It's likely that the woman who was the inspiration for the poem was Elinor Miriam White, his wife, although it is not necessary to know this for sure for the purposes of explaining the extended metaphor.

The silken tent sways in the breeze, but it is anchored securely by the "central cedar pole." This pole is firmly in the ground, and it "signifies the sureness of the soul." In other words, the woman represented by the silken tent is reliable because she has a strong soul. The vagaries of the summer breeze stand for the freedom that the woman enjoys, and the ropes that bind the silken tent represent the obligations that she has to husband, family, and society. In this way she is "loosely bound by countless silken ties of love and thought." It's only because of the pure freedom that the summer breeze represents that the woman becomes aware of the "slightest bondage."

In conclusion, we see that Frost uses this extended metaphor to give us the picture of a woman with a strong soul who is bound by the responsibilities of love that she has accepted but nevertheless also revels in her free spirit.