Aligner is pertaining to the type of semiconductor manufacturing equipment used to transfer patterns onto wafers through the use of photolithography and exposure. Aligners can "align" a new pattern on a reticle or mask to patterns already on the wafer, hence the name aligner. (see Step and Repeat, Step and Scan below)
Acceptor refers to the group three elements in the periodic table such as boron, B, aluminum, Al, gallium, Ga, or indium, In, have one less electron in the outer most energy level than silicon, Si. When these atoms are introduced into silicon, an impurity level is created near the valence band.
Bevel gear is characterized as gear of conical form designed to operate on intersecting axes. These gears allow transmission of poweraround corners so to speak as their shafts intersect. Most commonly the shafts will intersect at a 90° angle. Straight bevel gears have teeth that are straight, radially from the gears center point.
Angular bevel gear is characterized as a gear in which the axes are not at right angles.