"rokho" in Mahāparinibbānasutta

Namaste everybody,

translating some parts of the Mahāparinibbānasutta I has found the word
"rokho" in the sentence (DN 16, Mahāvaggapāḷi, Pukkusamallaputtavatthu):

"Tena rokho pana samayena pukkuso mallaputto āḷārassa kālāmassa sāvako
kusinārāya pāvaṃ addhānamaggappaṭippanno hoti."

But I can't find the translation of "rokho" in any dictionary. Do you know
what is the meaning of "rokho" and what root is it derived from?

Please kindly help

Best regards

Claus