Kaerikomu hodo o mo shirazu kanashiki wa yo o nagatsuki no wakare narikeri - Shika Wakashu(English Translation & Meaning)

帰り来む程をも知らず悲しきは
よをながつきの別れなりけり

Roma-ji: Kaerikomu hodo o mo shirazu kanashiki wa yo o nagatsuki no wakare narikeri
English Translation: Not knowing even
when it is you will return,
what makes it so sad
is that this is a parting
in the long nights of Nagatsuki.
Meaning: What makes it so sad, not knowing even when you will come back, is that ours is a parting in the Long Month, when the nights stretch on and on.
Commentary: Book Six Parting Poems 176

A poem on parting from someone who sets out in Nagatsuki, the ninth lunar month. The sorrow of a farewell whose return is uncertain is laid over the season of long autumn nights, and the length of the waiting is entrusted to the very name of the month.

First line, "kaerikomu": the conjectural "mu" points to the time when the traveler will presumably come back.
Second line, "hodo o mo shirazu": "hodo" means the time, and the added "mo" heightens the anxiety of not knowing even that.
Third line, "kanashiki wa" (what is sad), poses the question whose answer is revealed in the final line.
Fourth line, "yo o nagatsuki no": "yo o naga" is a pivot meaning both passing the night long and Nagatsuki, the Long Month. Following 175, which laments the aging of the one who waits, the length of the waiting here is folded into the name of the season.
Final line, "wakare narikeri": "keri" expresses sudden realization, and the poem closes by confirming the cause of the sorrow.
Source: Shika Wakashu
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