Omit in speech (5)
I believe the answer is:
elide
'omit in speech' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for elide that I've seen before include "Omit (syllable) in speech" , "Omit part of word" , "Omit (a sound or syllable) when speaking" , "Leave out, vowels perhaps" , "Omit vowel or syllable" .)