anacrusis

As a noun anacrusis

is (prosody) an unstressed syllable at the start of a verse.

As an adjective undefined is

lacking a definition or value.

In music|lang=en terms the difference between arsis and anacrusis

is that arsis is (music) the elevation of the hand, or that part of the bar at which it is raised, in beating time; the weak or unaccented part of the bar, opposed to the thesis while anacrusis is (music) an unstressed note or notes before the first strong beat (or downbeat) of a phrase.

As nouns the difference between arsis and anacrusis

is that arsis is the stronger part of a musical measure or a metrical foot while anacrusis is (prosody) an unstressed syllable at the start of a verse.

As nouns the difference between upbeat and anacrusis

is that upbeat is an unaccented beat at the start of a musical phrase while anacrusis is an unstressed syllable at the start of a verse.

As an adjective upbeat

is having a fast pace, tempo, or beat.

Metacrusis is likely misspelled.

Metacrusis has no English definition.

As a noun anacrusis is

an unstressed syllable at the start of a verse.

As a verb gerer

is to manage.

As a noun anacrusis is

(prosody) an unstressed syllable at the start of a verse.

As nouns the difference between anacrusis and anacruses

is that anacrusis is an unstressed syllable at the start of a verse while anacruses is plural of anacrusis.

As nouns the difference between anacrusis and anacusis

is that anacrusis is (prosody) an unstressed syllable at the start of a verse while anacusis is (medicine) total deafness.