1. [n]  riding a horse as a means of transportation
2. [n]  riding a horse as a sport
3. [adj]  traveling by wheeled vehicle such as bicycle or automobile e.g.; "the riding public welcomed the new buses"

Riding
Explores every aspect of horseback riding, from choosing the right school to preparing for competitions.

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1. \Rid"ing\ (r[imac]d"[i^]ng), n. [For thriding, Icel.
   [thorn]ri[eth]jungr the third part, fr. [thorn]ri[eth]i
   third, akin to E. third. See {Third}.]
   One of the three jurisdictions into which the county of York,
   in England, is divided; -- formerly under the government of a
   reeve. They are called the North, the East, and the West,
   Riding. --Blackstone.
   

2. \Rid"ing\, a.
   1. Employed to travel; traveling; as, a riding clerk. ``One
      riding apparitor.'' --Ayliffe.
   2. Used for riding on; as, a riding horse.
   3. Used for riding, or when riding; devoted to riding; as, a
      riding whip; a riding habit; a riding day.
   {Riding clerk}.
      (a) A clerk who traveled for a commercial house. [Obs.
          Eng.]
      (b) One of the ``six clerks'' formerly attached to the
          English Court of Chancery.
   {Riding hood}.
      (a) A hood formerly worn by women when riding.
      (b) A kind of cloak with a hood.
   {Riding master}, an instructor in horsemanship.
   {Riding rhyme} (Pros.), the meter of five accents, with
      couplet rhyme; -- probably so called from the mounted
      pilgrims described in the Canterbury Tales. --Dr. Guest.
   {Riding school}, a school or place where the art of riding is
      taught.
   

3. \Rid"ing\, n.
   1. The act or state of one who rides.
   2. A festival procession. [Obs.]
            When there any riding was in Cheap.   --Chaucer.
   3. Same as {Ride}, n., 3. --Sir P. Sidney.
   4. A district in charge of an excise officer. [Eng.]