To diminish gradually

ETYM as. tapur, tapor, taper; cf. Irish tapar, w. tampr.
(Homonym: tapir).
1. A convex shape that narrows toward a point.
2. The property possessed by a shape that narrows toward a point (as a wedge or cone).

1. Progressively narrowed toward one end
2. Furnished with or adjusted to a scale; graduated