Chrysler Correct Terminology ?

Hello, i have a question for Chrysler die-hards - an administrator from another Mopar forum said that the terms "big block" and "small block" were originally Chev terms, coined by GM or Chev people. And that 'Chrysler correct' is actually what Chrysler use themselves, which is A engine (poly), LA (Light A), B, RB (Raised B), Wedge, Hemi, Magnum..etc etc Does anyone know for sure if this is correct?

Or are SB and BB just generic terms which can be used with all Detroit production engines...with their origin lost in the mists of history?

Informative answers ... No guessing please!