Source : Webster's Revised Unabridged Dictionary (1913)

Prickly \Prick"ly\, a.
   Full of sharp points or prickles; armed or covered with
   prickles; as, a prickly shrub.

   {Prickly ash} (Bot.), a prickly shrub ({Xanthoxylum
      Americanum}) with yellowish flowers appearing with the
      leaves. All parts of the plant are pungent and aromatic.
      The southern species is {X. Carolinianum}. --Gray.

   {Prickly heat} (Med.), a noncontagious cutaneous eruption of
      red pimples, attended with intense itching and tingling of
      the parts affected. It is due to inflammation of the sweat
      glands, and is often brought on by overheating the skin in
      hot weather.

   {Prickly pear} (Bot.), a name given to several plants of the
      cactaceous genus {Opuntia}, American plants consisting of
      fleshy, leafless, usually flattened, and often prickly
      joints inserted upon each other. The sessile flowers have
      many petals and numerous stamens. The edible fruit is a
      large pear-shaped berry containing many flattish seeds.
      The common species of the Northern Atlantic States is
      {Opuntia vulgaris}. In the South and West are many others,
      and in tropical America more than a hundred more. {O.
      vulgaris}, {O. Ficus-Indica}, and {O. Tuna} are abundantly
      introduced in the Mediterranean region, and {O. Dillenii}
      has become common in India.

   {Prickly pole} (Bot.), a West Indian palm ({Bactris
      Plumierana}), the slender trunk of which bears many rings
      of long black prickles.

   {Prickly withe} (Bot.), a West Indian cactaceous plant
      ({Cereus triangularis}) having prickly, slender, climbing,
      triangular stems.

   {Prickly rat} (Zo["o]l.), any one of several species of South
      American burrowing rodents belonging to {Ctenomys} and
      allied genera. The hair is usually intermingled with sharp
      spines.

Source : WordNet®

prickly heat
     n : obstruction of the sweat ducts during high heat and humidity
         [syn: {heat rash}, {miliaria}]