The name is of Polish origin (or at least, the person who used it was definately Polish).
Phonetically, it would be MATT-YAY or something quite similiar.
I think it is spelt “Matje” normally.
Now, is this a name for a male or female in Poland (and/or Eastern European countries)?
Just as in English John is almost always male, and Jane is nearly always female, what is the name “Matje” in Poland?
Also, bear in mind I COULD have the EXACT spelling wrong - I just gave the most likely one because this is how I remember seeing it spelt somewhere.
The pronounciation as mentioned above is something along the lines of “Matt-Yay” or “Matay” etc.
I don’t speak Polish, but I’d make an educated guess that it’s a diminutive, and male. My reasoning is that many of the Slavic languages form diminutives in -ya and -sha, and Russian “Matya” – an obviously close cognate – is “Matty” – meaning the English diminutive for Matthew. (I’ve forgotten the Russian precise-name parallel to Matthew, much less the Polish if I ever knew it, but I do recall that Matya is the diminutive form; an emigré family I grew up knowing, the son had a friend back in the old country by that nickname whom he used to speak of.)
How would that be pronounced, Cap’n? My impression would be “MAT-see-yay” which would match what the OP said, more or less, but I could be quite wrong.
In that case, since I actually am familiar with Slavic palatalized consonants, I suspect the Maciej I know has been giving an Anglicized pronunciation of his name for American ears.