free verse 
noun [mass noun]
Poetry that does not rhyme or have a regular rhythm: a poem written in free verse...Also called vers libre.
- He says he is on a mission to make poetry popular again, and to undo what he says is the damage done by free verse, or poetry without regular patterns of rhyme, meter or stanzas.
- Others have suggested that Anglo-American writers generally did not distinguish between free verse and prose poems.
- Many of these complainers are writers of free verse poems who complained vigorously when new formalists declared that free verse wasn't real poetry - that poetry was rhymed and metered and used traditional forms.