Meter :]

Definition:  is the basic rhythmic structure of a verse or lines in verse

Significance: Meter brings feelings and emotions to readers while reading. It also makes a poem has tone and rhyme. It makes the poem interesting to read.

Example:

Anapestic Tetrameter
from "The Destruction of Sennacherib," by George Gordon Lord Byron

........1.......................2..........................3......................4
The As SYR..|..ian came DOWN..|..like the WOLF..|..on the FOLD,
........1.......................2..........................3....................4
And his CO..|..horts were GLEAM..|..ing in PUR..|..ple and GOLD; 
.........1.........................2.............................3.......................4
And the SHEEN..|..of their SPEARS..|..was like STARS..|..on the SEA 

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