PSAT 10 and PSAT/NMSQT are exactly the same, except the 10 is taken in spring of 10th grade (and has percentiles accordingly), and the NMSQT is taken in fall of 10th or 11th grade (and has norms accordingly). If you take it in the fall, it is the NMSQT by definition, regardless of nominal grade. There are norms for nationally representative 10th-, and 11th-graders, and taken from actual test-takers.

https://collegereadiness.collegeboa...ing-the-tests/compare-psat-nmsqt-psat-10

https://collegereadiness.collegeboard.org/pdf/psat-nmsqt-understanding-scores.pdf

...pronounced like the long vowel and first letter of the alphabet...