D defs.my
Entry 1 sense Webster, 1913

Assibilation

· As·sib·i·la·tion · IPA /əˌsɪbɪˈleɪʃən/
01 n. Change of a non-sibilant letter to a sibilant, as of -tion to -shun, duke to ditch.
  1. 1.
    Change of a non-sibilant letter to a sibilant, as of -tion to -shun, duke to ditch.