Every Monday we will post an entry that hasn’t yet been published with a view towards harnessing the collective onomastic power of the internet. If you have any thoughts about the name’s origin, other variants it might be related to, other examples of its use, etc., please share them in the comments! If you wish to browse other Mystery Monday names, there is an index.
Today’s name is the name of an 8th C Dutch abbess; she shows up in a variety of historical records, but as far as we can tell she is the sole example of this name. Hapax legomena are always tricky to determine etymologies for, but it’s always worth asking in case there’s an expert out there who has a suggestion!
Do you recognize the name? Or know of any other examples of it? Please share your thoughts in the comments!
Dictionary of Medieval Names from European Sources 
Förstemann (1900) speculates, using very hedging language, if the name can have a prototheme BLAND, cognate to the modern English verb to blend “to mix”. The real problem is the deuterotheme and Förstemann thinks of a different reading as Blendunivi—the deuterotheme in this case is NIVI “new”, a well-attested second part of feminine names.
The stem Bland itself is not purely Germanic, it also occurs in Celtic names and the name Blandina is of Latin origin.
There is a genitive Blandmundi in the href=”https://archive.org/details/libriconfraterni00eato/page/208/mode/2up?q=blandmundi”Libri confraternitatum Sancti Galli. I’d want to see the original hand before venturing any further afield for the deuterotheme.