One day last month I posted a very obscure word on my web page:

the worthless word for the day is: noctuolent

[fr. L. noctu, by night + olent, redolent of]
obs. rare of a flowering plant: more strongly
scented at night than during the day

"Dog-rose, The noctuolent plants, of which there
are several kinds, as some of the geraniums, and
of the jasmines, etc."
- Ephraim Chambers, Cyclopędia (Suppl. 1753)

"noctuolent (NOK-too-o-lent) smelling strongest
at night - the noctuolent bog on the property"
- David Grambs, The Endangered English Dictionary

not to be confused with noctilucent (luminescent at night or in the dark, also rare in this sense)

How obscure is this? 11 ghits, 5 of which are attributable to me, and only one of which has any cachet (the Chambers ref.); one(1) hit at Google Books, from the Grambs word book.

Now comes the fun part. The index of the Grambs book has this:
"night, smelling strongest at: NOCTUOLUCENT"

googling, noctuolucent gets 73(!) ghits, amongst which the most damaging is, of course, from the same index, at an amazon.com review:
So if you are looking for a compact way to describe something--a flower, say--that smells strongest at night, try "noctuolucent."

It's a lot easier to foist a non-word on the unsuspecting masses these days.