Language, to a considerable extent, is concealed figuration: ironies and synecdoches, metonymies and metaphors that we recognize only when our awareness increases. Real poetry is aware of and exploits these ruined tropes, though it is both a burden and a resource, for later poets in a tradition, that language ages into this wealth of figuration. The major poets of the twentieth century, in Britain and America, were those who could best exploit this equivocal richness: Thomas Hardy, W. B. Keats, D. H. Lawrence, Robert Frost, T. S. Eliot, Wallace Stevens, and Hart Crane among them. 
For some reason this afternoon the word evening suddenly struck me. It's a great word. The word afternoon is so exact and straightforward that it lacks any mystery. There is something businesslike about it that fits. But evening has something mysterious about it, something almost sinister (The Evening would make for a perfect name for a triller on the New York Times Bestseller list). The name suggests movement, action. Something is going on. It's a good name for a time of day whose cousin is twilight.
I've been trying to think of how evening is used in poetry and I can think of two examples, even without the aid of Google.
There is a prayer by St. Patrick that I like a lot, whose title is usually translated "The Breastplate of St. Patrick" though not always. The following lines are taken from a version, with Victorian liberties taken, by the nineteenth century Anglican hymn writer Cecil Frances Alexander:
I bind unto myself today
The virtues of the starlit heaven,
The glorious sun's life-giving ray,
The whiteness of the moon at even,
The flashing of the lightning free 
The line that is most memorable to me is "The whiteness of the moon at even." As the original's version is much less verbose ("étrochtai ésci" is all it takes for St. Patrick to say the same thing ), Oliver Davies' translation "in Moon's radiance" is more accurate , and I like the simplicity (how else can you describe such great and intricate things, sometimes, without simplicity). And let's face it, not many people go for the Victorian aesthetic these days. But there is something haunting about the line "the whiteness of the moon at even."
The Anglicans might have been onto something for calling Vespers Evensong, which reminds me of another hymn, an ancient beautiful hymn, from Vespers:
O Joyful Light of the holy glory of the immortal, heavenly, holy blessed Father, O Jesus Christ. Having come to the setting of the sun, having beheld the evening light, we hymn the Father, Son, and Holy Spirit, God. Meet it is at all times to hymn Thee with reverend voices, O Son of God, Giver of Life, wherefore the whole world doth glorify Thee. 
Chesterton wrote once that "Mysticism keeps men sane. As long as you have mystery you have health; when you destroy mystery you create morbidity. The ordinary man has always been sane because he has always been a mystic. He has permitted the twilight."  And somehow the evening with its mystery and its sanity, which is so important for those of us who during the day do the world's work the best we can with keyboards and coffee and office cubes and copiers, is wrapped up in and evoked by its name, which is kind of neat.
 Bloom, Harold. The Art of Reading. Perennial. New York, NY: 2005. And great little book, which as has the advantage of being little. You don't have to buy it; you can just read it in the coffee shop of your local corporate bookstore.
 translated by Oliver Davies in Celtic Spirituality (The Classics of Western Spirituality). Paulist Press. Mahwah, NJ: 1999.
 chapter 2 of Orthodoxy