What is the metaphorical meaning of the word "yellow" in "The Road Not Taken" by Robert Frost?
There are several possible meanings for Robert Frost's use of the word yellow in his poem "The Road Not Taken." If you look at the poem itself, Frost chooses to open up with that seemingly small, but most likely symbolic adjective:
Two roads diverged in a yellow wood,
And sorry I could not travel both
And be one traveler, long I stood
And looked down one as far as I could
To where it bent in the undergrowth.
The literal interpretation of the use of yellow here indicates that the narrator of the poem is strolling along in a forest during the autumn, when all of the leaves change colors. However, if you look at the overall symbolism of the poem itself--that the forest is life, and the paths we take are the decisions that we make--we can apply a figurative meaning to the fact that the leaves are yellow. If life is like a forest, then our birth is probably comparable to springtime: young, fresh, new, green, growing quickly. By the time the seasons have changed to autumn, in life, that means we are probably a bit older, and from then on, diminishing in vitality and growth.
Knowing this, it also helps to know a bit of background on Robert Frost. He did not become well-known for his writing and publications until later in his life--in the autumn of his life. He wasn't young anymore. So, if he was writing this poem, making the forest autumn compares to the fact that he himself was in the autumn of his life. The person traveling this road is not young, but older.
Secondly, when people come to crossroads and deeply contemplate major decisions, as this poem seems to indicate is happening at the time, the decisions we make often have lasting and final impacts. After autumn, there is winter, where no life, no change, no growth and no redemption occurs. The decision the narrator is wrestling with could be one of those serious ones that, once made, will "finalize" the course the rest of his life will take. This is supported in the third stanza where Frost knows that if he takes one path over another, he does so "knowing how way leads on to way" and then says of that decision, "I doubted if I should ever come back." He indicates that he knew taking one path was a one-way street that wouldn't allow him to come back. This finality is reflected in the yellow leaves; it is autumn, the season right before the finality of winter. So that is another possible metaphorical meaning, other than autumn symbolizing the stage of life the narrator is in.
I hope that those thoughts help to get you started; good luck!