History: What does a multi-pressor do?

What does a multi-pressor do?

• A multi-pressor is a collection of individual compressors for specific frequency ranges.
  Excellent!
• A multi-pressor increases the amplitude over a threshold.
  That is an expander.
• A multi-pressor reduces the amplitude over a threshold.
  That is a compressor.
• A multi-pressor targets a specific band of frequencies and reduces the amplitude on specific ranges.
  That is a de-esser.