Axis. An imaginary line on which a body turns.
Axis of rotation. An imaginary line round which anything turns or spins.
Axle. A wood or metal rod on which one or more wheels turn, or it may turn with the wheel or wheels.
Badge of merit. A badge awarded by the organization of Boy Scouts to members who can show a certain amount of skill in doing certain things. [See Appendix A].
Band. (1) A flat strip of any material, or (2) such a strip whose ends are joined together.
Beam. Rays of light which are parallel. See Ray.
Bearing. (1) A piece of metal, or a bit of agate or other jewel, on which a pivot, spindle or shaft turns. (2) A direction as found by the Sun or stars, or by the compass, sextant or other means.
Body. Any separate and distinct amount of matter when held together. The Sun and Moon are heavenly bodies.
Degree. (1) The 360th part of a circle. (2) Indicated by this sign °.
Device. (1) An apparatus or instrument or any part thereof. Any arrangement for producing a given result.