Noun

1. A form of physical punishment in which a beating is applied to the buttocks.

   Domestic spanking is often endured over the knee (or lap), formal spanking rather applied over a contraption such as a tresle or A-frame, with or without constraints

2. An incident of such punishment, or such physical act in a non-punitive context, such as a birthday spanking.

   During bare-butt spankings one clearly sees the bottom-skin turn red or even purplish

Adjective

1. Relating to spanking(s); e.g. inclined to punishment by spanking

   The notoriously spanking headmaster ordered fresh birches every term

2. An intensifier.

   brand spanking new

   a spanking good time

3. Fast and energetic.

   a spanking pace

4. Brisk and fresh.

   a spanking breeze

5. remarkable of its kind.