English

Noun

transition zone ‎(plural transition zones)

1. Any of several physical zones in which the properties, or the behaviour of something undergoes a radical change
   1. (physics) The stage in the flow or a fluid during which it changes from laminar to turbulent
   2. (geology) The region between the upper and lower mantle characterized by a rapid increase in density
   3. The area between a central business district and residential housing in a city