Definition of initialese in US English:

initialese

noun

informal
  • Abbreviations formed from the initial letters of the shortened words.

    ‘students of hospital language have noticed how doctors have become addicted to initialese’
    • ‘But Miss Cleary, of Nashville, in her song ''I.M. Me,'' has engaged in text messaging, a combination of initialese and the euphonic use of the alphabet that deserves scholarly attention.’
    • ‘Terms, definitions, and contracted phrases can pile up into a meaningless mess of initialese and confusion when you're about the business of conducting a flight under instrument conditions.’

Pronunciation

initialese

/iˌniSHəˈlēz/