I have never heard the phrase, but I am not called 'nana', or anything similar. Whether I sometimes have a nap depends on how well I slept the previous night, and frequency, length and when varies and on many days I do not have one.
Yesterday was an extreme. I had a migraine brewing and took a couple of paracetomol and codeine, the only pain killer that works. I fell asleep for an hour, but woke up pain free.
I nap at a table, not in an armchair. I cross my arms on the table top, rest my head on my arms,
. I do it that way in order to make sure I do not sleep too deeply or too long. For me a 'normal' nap is 10 minutes.