Meaning of regressive assimilation

regres'sive assimila'tion

Pronunciation: [key]
— Phonet. Phonet.
  1. assimilation in which a following sound has an effect on a preceding one, as in pronouncing have in have to as (haf&hasp;), influenced by the voiceless (t) in to. Also calledCf.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.