The word 'custom' (מנהג) is spelled with the same letters as 'Gehinnom' (גהנ"ם).

מנהג אותיות גהנ"ם
Shiurim in this topic
2675. Unless you take out all items I noted you have no permission to say that I saw the manuscript Unless you take out all items I noted you have no permission to say that I saw the manuscript