1. The act of ascending; a rising; ascent.
3. An ascending or arising, as in distillation; also that which arises, as from distillation. Vaporous ascensions from the stomach. (Sir t. Browne) ascension day, the Thursday but one before Whitsuntide, the day on which commemorated our Savior's ascension into heaven after his resurrection; called also holy Thursday.
(Science: astronomy) right ascension, an arc of the equator, intercepted between the first point of aries and that point of the equator which rises together with a star, in an oblique sphere; or the arc of the equator intercepted between the first point of aries and that point of the equator that comes to the horizon with a star. It is little used in modern astronomy.