3. The first word of “The Star-Spangled Banner” “Oh” is an example of the literary device known as anacrusis, a lead-in syllable or syllables that precede the first full foot.    From Wordnik.com.  [2008 August 15 « One-Minute Book Reviews] Reference

This may be trochaic with anacrusis or iambic with feminine endings, but neither quite adequately describes it.    From Wordnik.com.  [The Principles of English Versification] Reference

Similar combinations, still freer, with frequent anacrusis as well, are characteristic of Swinburne's Hesperia; e. g.    From Wordnik.com.  [The Principles of English Versification] Reference

If the first two syllables be regarded as anacrusis, the first line would be trochaic, with a dactyl substituted for a trochee in the second foot.    From Wordnik.com.  [The Principles of English Versification] Reference

The four stresses of the Anglo-Saxon verse are retained, and as much thesis and anacrusis is allowed as is consistent with a regular cadence.    From Wordnik.com.  [The Translations of Beowulf A Critical Bibliography] Reference

Possible, of course; but treat them as Ionics a minore with an anacrusis, and see if they don't go better. ".    From Wordnik.com.  [The Private Life of Henry Maitland]

‘Possible, of course; but treat them as Ionics a minore with an anacrusis, and see if they don’t go better.’.    From Wordnik.com.  [New Grub Street] Reference

According to Tristan Jakob-Hoff, Chailly has taken his own pencil to the score and replaced the single-note Thwack! with a "short, anacrusis before each note - 'buh-duh-DUM!.    From Wordnik.com.  [ArchitectureChicago PLUS] Reference