The Collaborative International Dictionary
Anacrusis \An`a*cru"sis\, n. [Gr. ?, fr. ? to push up or back; ? + ? to strike.] (Pros.) A prefix of one or two unaccented syllables to a verse properly beginning with an accented syllable.
Douglas Harper's Etymology Dictionary
"unstressed syllable at the beginning of a verse," 1833, Latinized from Greek anakrousis "a pushing back," of a ship, "backing water," from anakrouein "to push back, stop short, check," from ana- "back" (see ana-) + krouein "to strike," from PIE *kreue- (2) "to push, strike" (cognates: Russian krusit, Lithuanian krusu "to smash, shatter," Old Church Slavonic kruchu "piece, bit of food," Old English hreowian "feel pain or sorrow," Old Norse hryggja "make sad").
n. 1 (context prosody English) An unstressed syllable at the start of a verse. 2 (context music English) An unstressed note or notes before the first strong beat (or downbeat) of a phrase.
In poetry and music, and by analogy in other fields, an anacrusis (plural anacruses) is a brief introduction.
Anacrusis is a Progressive Thrash metal band from St. Louis, Missouri, USA. Anacrusis was one of the first bands to attempt to blend thrash and progressive metal. Their albums Manic Impressions and Screams and Whispers are considered as classics of the progressive thrash metal / prog metal genre.
Anacrusis is a genus of moths belonging to the subfamily Tortricinae of the family Tortricidae.