Dasher is one of Santa's reindeer his name originated from the 1823 poem by Clement C. Moore "A Visit from St. Nicholas" (also known as "The Night Before Christmas" or "'Twas the Night Before Christmas") is largely credited for the contemporary Christmas lore that includes the eight flying reindeer and their names.[4]
The relevant segment of the poem reads:
when, what to to my wondering eyes should appear,
but a miniature sleigh, and eight tiny rein-deer,
with a little old driver, so lively and quick,
I knew in a moment it must be St. Nick.
More rapid than eagles his coursers they came,
And he whistled, and shouted, and call'd them by name:
"Now, Dasher! Now, Dancer! Now, Prancer, and Vixen!
"On, Comet! On, Cupid! On, Dunder and Blixem!
"To the top of the porch! to the top of the wall!
"Now dash away! dash away! dash away all!"
As dry leaves that before the wild hurricane fly,
When they meet with an obstacle, mount to the sky;
So up to the house-top the coursers they flew,
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