Saewataru hikari o shimo ni magaete ya tsuki ni utsurou shiragiku no hana - Senzai Wakashu(English Translation & Meaning)

冴えわたる光を霜にまがへてや
月にうつろふ白菊の花

Roma-ji: Saewataru hikari o shimo ni magaete ya tsuki ni utsurou shiragiku no hana
English Translation: The light so clear and cold,
has it mistaken it for frost?
in the moon's own light
how it changes as it fades,
the white chrysanthemum
Meaning: Has it mistaken the clear, cold light for frost? The white chrysanthemum changes its color in the moonlight.
Commentary: Book Five Autumn Poems II 350

Headnote: "Composed as a poem on chrysanthemums when composing a hundred-poem sequence"
Composed as a poem on chrysanthemums when the poet was writing a hundred-poem sequence. Has it mistaken the cold, clear moonlight for frost, he asks, for the white chrysanthemum changes color in the moonlight. White chrysanthemums were said to turn purple when touched by frost, and the conceit lies in attributing that change not to frost but to moonlight.
The author, "Fujiwara no Ietaka," was the son of Provisional Middle Counselor Fujiwara no Mitsutaka. He studied poetry under Fujiwara no Shunzei and became one of the compilers of the Shin Kokin Wakashū. A poem of his is included in the Ogura Hyakunin Isshu.
The five poems from 346 through 350 of this book are poems on chrysanthemums, and 346, 348 and 350 all end with "shiragiku no hana," the white chrysanthemum.

First line, "saewataru": "clear and cold throughout," the chill of the moonlight.
Second line, "hikari o shimo ni": "the light as frost," presenting the likening of light to frost.
Third line, "magaete ya": "magau" is to be indistinguishable or to mistake, and "ya" is interrogative, personifying the chrysanthemum, "did it mistake the moonlight for frost?"
Fourth line, "tsuki ni utsurou": "utsurou" is to change color, sharing the word with "utsuroeba" in the preceding poem, 349, on the changing chrysanthemum.
Fifth line, "shiragiku no hana": ending on a noun, the same last line as 346 and 348 of this book. With it the run of chrysanthemum poems is closed.
Author: Fujiwara no Ietaka
Source: Senzai Wakashu
Prev Poem: Asanaasana magaki no kiku no utsuroeba tsuyu sae iro no kawariyuku kana
Next Poem: Kotogoto ni kanashikarikeri mube shi koso aki no kokoro o urei to iikere