Onozukara yogaruru toki no samushiro wa namida no uki ni naru to shirazu ya - Kinyo Wakashu(English Translation & Meaning)

おのづから夜離るる時のさむしろは
涙のうきになると知らずや

Roma-ji: Onozukara yogaruru toki no samushiro wa namida no uki ni naru to shirazu ya
English Translation: When on chance nights
you fail to come to me,
my narrow, cold mat
is set afloat in tears;
don't you know how sad it is
Meaning: On those nights when, as it happens, you stay away, don't you know that my narrow, cold mat floats in tears and becomes a thing of sorrow?
Commentary: Book Seven Love Poems I 390

On nights when, even by chance, the beloved fails to come, the mat of the lonely bed floats in tears and becomes a thing of sorrow; the poet reproaches the other for not knowing it. With samushiro holding samushi, cold, and uki meaning both floating and sorrowful, the poem conveys the cold and pain of sleeping alone.
Some manuscripts give the headnote 'Sent to someone.'
The author, Akinaka, is Minamoto no Akinaka. A son of the Minister of the Right Minamoto no Akifusa, he rose to Head of the Council of Divinities and was one of the poets of the Horikawa Hundred-Poem Sequences.

First line, 'onozukara', means by chance.
Second line, 'yogaruru toki no', means at times when you stay away at night.
Third line, 'samushiro wa', is a pivot word in which samushiro means both samushiro, a narrow mat, and samushi, cold, left in kana. Like 'inamushiro' in poem 353 in this book, it sings of a mat.
Fourth line, 'namida no uki ni', is a pivot word in which uki means both uki, floating in tears, and uki, sorrowful, left in kana. 'Uki wa waga mi ni' in poem 417 in this book uses the same pivot word.
Final line, 'naru to shirazu ya', means do you not know it becomes so, the particle ya posing the question to the other.
Author: Minamoto no Akinaka
Source: Kinyo Wakashu
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