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blank verse vs. free verse

[blangk vurs] / ˈblæŋk ˈvɜrs /

noun

  1. unrhymed verse, especially the unrhymed iambic pentameter most frequently used in English dramatic, epic, and reflective verse.

[free vurs] / ˈfri ˈvɜrs /

noun

Prosody.
  1. verse that does not follow a fixed metrical pattern.