acrophony
/əˈkrɒfəni/ /əˈkrɒf(ə)ni/noun
The use of a graphic symbol originally representing a word (or the object to which it refers) to denote the initial syllable or sound of that word.
- Such a change in the application of a set of symbols was the basis of alphabetic writing..
Origin
Late 19th century. From acro- + -phony. Compare earlier acrophonetic, acrophonic.