\Ax"le\ ([a^]ks"'l), n. [OE. axel, exel, shoulder, AS.
eaxl; akin to AS. eax axle, Sw. & Dan. axel shoulder, axle,
G. achse axle, achsel shoulder, L. axis axle, Gr. 'a`xwn,
Skr. aksha, L. axilla shoulder joint: cf. F. essieu, axle,
OF. aissel, fr. dim. of L. axis. [root]205. Cf. 2d {Axis}.]
1. The pin or spindle on which a wheel revolves, or which
   revolves with a wheel.
2. A transverse bar or shaft connecting the opposite wheels
   of a car or carriage; an axletree.
3. An axis; as, the sun's axle.
         Had from her axle torn The steadfast earth.
                                               --Milton.
Note: Railway axles are called leading and trailing from
      their position in the front or in the rear of a car or
      truck respectively.