Naming a letter of the alphabet by using a word whose initial sound is the sound represented by that letter

WordNet Word definitions in WordNet
n. naming a letter of the alphabet by using a word whose initial sound is the sound represented by that letter

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Acrophony \A*croph"o*ny\, n. [Gr. 'a`kros extreme + ? sound.] The use of a picture symbol of an object to represent phonetically the initial sound of the name of the object. [1913 Webster] ||

Wiktionary Word definitions in Wiktionary
n. Naming letters in an alphabetic writing system using words whose initial sounds are represented by the respective letters.

Wikipedia Word definitions in Wikipedia
Acrophony (; Greek: ἄκρος akros uppermost + φωνή phone sound) is the naming of letters of an alphabetic writing system so that a letter's name begins with the letter itself. For example, Greek letter names are acrophonic: the names of the letters α, β, ...