Prosiopesis (from Ancient Greek Greek, Ancient (to 1453);: προσιώπησις 'becoming silent') is a term coined by Otto Jespersen for pronouncing a word or phrase without vocalizing its initial sounds. One example Jespersen gave is for "Good morning" to be shortened to "Morning". Jespersen introduced the idea in 1917 in Negation in English and Other Languages (p. 6);[1] he also discusses it in The Philosophy of Grammar (; reprint 1992). Prosiopesis is studied as a mode for originating interjections, which can shed light on their meaning.
This is similar to aposiopesis, where the ending of a sentence is deliberately excluded. David Crystal writes, "In rhetorical terminology, an elision in word-INITIAL position was known as aphaeresis or prosiopesis, in word-MEDIAL position was known as syncope, and in word-FINAL position as apocope."[2]