I wonder which one it is?
A bit of both, actually, although I wouldn't choose your exact wording.
There is also a third criterion. It is a speed that incorporates the speed increment that inevitably occurs, before the speed and flight path angle can be stabilized, when the airplane is rotated at VR at a normal rate with all engines operating, just as V2 incorporates the inevitable speed increment when rotated at VR with one engine inoperative.
P.S.
An additional consideration may result from FAR Part 36: Noise Standards, Appendix B:
(4) The takeoff reference speed is the all-engine operating takeoff climb speed selected by the applicant for use in normal operation; this speed must be at least V2+10kt (V2+19km/h) but may not be greater than V2+20kt (V2+37km/h). This speed must be attained as soon as practicable after lift-off and be maintained throughout the takeoff noise certification test.