The term ‘nonogram’ crops up in other fields on various WWW pages. I'm pretty sure at least some of these uses of the word are being confused with, or mistyped instead of:

• ‘nomogram’ (some type of graph or chart, I gather),

• ‘nanogram(me)’ (a fractional unit of weight/mass), or

• ‘nonagram’ (a nine-pointed star, or a nine-letter signature),

…but I could be wrong. If I'm right, though, it really screws up the search engines.

I've also seen ‘Nonogram’ used to mean a word puzzle where you try to make as many different words as you can from one given letter and at least three others from eight.