What does "ascensional" mean?

Ascensional: Relating to ascension; connected with ascent; ascensive; tending upward; as, the ascensional power of a balloon. Ascensional difference (Astron.), the difference between oblique and right ascension; -- used chiefly as expressing the difference between the time of the rising or setting of a body and six o'clock, or six hours from its meridian passage.