Let's muddy the waters some more.
The mfg ( DeVinci) calls the bike I bought last year - "Stellar Acera" - an XC- Sport model since it has XC-Sport geometry. No, I have no idea how that is defined.
But some would call it a Hard-tail MTB for the obvious reasons. 3x9 gear train, straight handlebar etc. I call it the perfect bike for all the riding I do. From pavement to gravel to a bit of single track.