What is the meaning of praeprimis?

Question

I came across the word "praeprimis" when reading some 17th century Latin (Experimenta nova, Otto von Guericke, b. 4 ch. 15 ). To my best guess, it's a combination of "praecipue" and "imprimis", and I think it's used the same way, when I search for the term through Google Books. Is this likely? Or does the word have a meaning of its own?

Edit: the relevant passage is describing the so-called "virtus lucens", part of Guericke's model for the universe, observed by rubbing a sulphur globe with a dry hand, which works best at night in the dark.

Ad Virtutem Lucentem quod attinet, ea simili ratione in hoc globo se prodit. Nam si eum in conclave obscurum tecum conferas et palmâ siccâ præprimis noctu, atteras, eâdem ratione lucet, quâ saccharum si tundatur.

Answer 1

It is a modern synonym for imprimis, meaning foremost. It can also be used to begin a list of items, like in a treaty or legal will document. (Note that in modern scientific Latin, imprimis is often used to mean "essentially" or "especially.")

In the Reyher and Juncker lexicon, it says the following about the word:

Praeprimis, quasi Aduerb. pro, imprimis, vox recentissimae aetatis. N.

It is possible the new word was introduced in the age of printing to avoid confusion with the word imprimo, which means to print in modern Latin.