Mo*men"tous (?), a. [Cf. L. momentosus rapid, momentary.] Of moment or
consequence; very important; weighty; as, a momentous decision;
momentous affairs. -- Mo*men"tous*ly, adv. -- Mo*men"tous*ness, n.
Mo*men"tum (?), n.; pl. L. Momenta (#), F. Momentums (#). [L. See
Moment.] 1. (Mech.) The quantity of motion in a moving body, being
always proportioned to the quantity of matter multiplied into the
velocity; impetus.