prosiopesis
/ˌprɒsɪə(ʊ)ˈpiːsɪs/Grammar
noun
Ellipsis of the beginning of a grammatical structure in speech or writing.
Origin
1920s; earliest use found in Otto Jespersen (1860–1943), linguist. From pro- + Greek σιώπησις taciturnity, in scholia (medieval Greek or earlier) on Ptolemy Tetrabiblos 160 from ancient Greek σιωπᾶν to be silent + -σις; compare quot. 1922.