A PUSHING BACK

Anacrusis is a technical term in poetry and music wherein one syllable or note is unstressed at the beginning of a verse or bar line, respectively. The word was first used in an 1833 issue of The Edinburgh Review when describing the theory of iambic pentameter. This was a loanword from Latin, and the Latin word was a transliteration of an Ancient Greek word, anakrousis. This meant "a pushing back" or "pushing up", presumably because the transition to stressed sounds with the next syllable/note will be like pushing upwards. Ana- here means "back" and comes from the Proto-Indo-European root an, meaning "on" or "above". Meanwhile, the root of the word, krouein, meant "to strike" and comes from PIE kreue, also "strike" or "push". Usage of anacrusis peaked in the 1960s and has been trending downward since.