This probably came from a country with transliterations that don’t line up very well in English. Like Japanese doesn’t have an English r, so one of the ways they do it is to elongate a vowel and alarm would become alaamu. But sometimes they have a long vowel with no r, like smoke is sumo-oku.

When they go to write in English it’s not clear whether that long vowel represents an r or not, and they chose to add it in smoke and drop it in alarm. I still run across a smorking room from time to time.

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