Kimi kouru namida shi nakuwa karakoromo mune no atari wa iro moenamashi - Kokin Wakashu(English Translation & Meaning)

君恋ふる涙しなくは唐衣
胸のあたりは色燃えなまし

Roma-ji: Kimi kouru namida shi nakuwa karakoromo mune no atari wa iro moenamashi
English Translation: Were it not for tears
that I shed in longing for you,
my Chinese robe,
around the breast at least,
would flare up in fiery hues.
Meaning: If it were not for the tears I weep in longing for you, the breast of my fine robe would surely be burning red with the fire of love.
Commentary: Book Twelve Love Poems II 572

Headnote: "A poem from the poetry contest held at the residence of the Empress in the Kanpyō era"
The poet says that were it not for the tears he sheds in longing, the breast of his robe would flare up in color from the fire of love burning in his heart. Using the conceit of omoi, love, containing hi, fire, and the counterfactual idea that tears are extinguishing that fire, he expresses both the abundance of his tears and the intensity of his feelings. It was composed for the Kanpyō-era Empress's poetry contest and is placed within the run of poems from that contest. The poems from that contest in this book end with this one.
Ki no Tsurayuki was a poet of the early Heian period, the son of Ki no Mochiyuki. He was the leading compiler of the Kokinshū and wrote its Japanese preface. He served as Governor of Tosa and is also known as the author of the Tosa Diary, which records his journey back to the capital. He is one of the Thirty-Six Poetic Immortals.

First line, "kimi kouru": "longing for you," modifying "tears" in the second line. It shares its first line with 567 of this book, and as poems from the same contest they also share the exaggeration of tears.
Second line, "namida shi nakuwa": shi is an emphatic particle, and nakuwa, the continuative of nashi with the particle wa, forms a hypothesis: "if there were no tears."
Third line, "karakoromo": karakoromo, a "Chinese robe," is an elegant word for a garment, leading into "around the breast" in the fourth line.
Fourth line, "mune no atari wa": the breast is where love burns, overlapped with the breast of the robe.
Fifth line, "iro moenamashi": na is the conditional of the completion auxiliary nu and mashi expresses the counterfactual: "it would surely have taken on a burning color." The poem closes on the idea that tears are putting out the fire of love.
Author: Ki no Tsurayuki
Source: Kokin Wakashu
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