Identifying function words

[farmerjohn]

daiin is illī, d stands for l sound and aiin for long o (n marks long vowels)
So common ending -dy stands for -ellus, and -ody for -ulus, diminuitive forms often used in medieval latin. Interestingly, -ody is very rarely used in bathing section, so this gives us at least three(!) authors

I think it's very unlikely that such a large proportion of words in a manuscript with several differently themed sections would all end in -ellus.

In fact, since you referenced medieval Latin abbreviations, if it were such, then -dy has many possible interpretations, including -bz (-bus) or -rum or even a category designation as it was done in Hildegard von Bingen's code, but... what is important to remember is that even if the VMS includes Latin-based glyphs or even Latin scribal conventions, it doesn't necessarily mean it's Latin (the conventions could be used to mean something else and were also used to mean other things in other languages even when the same symbols were used).

I think it's all about peculiar form of Latin used in VMS and extensive use of diminuitive suffices is its significant trait. And different authors of manuscript used different suffices. The one who wrote balneo section never used -ulus, only -ellus. That's why words chedy and shedy appear only and mostly in this section respectively. Other authors used these words with suffix -ulus and got sheody and cheody. voynechese.com gives a nice picture of it.