Vignette is a French word meaning “little vine”.
A vignette is a short narrative sketch using evocative figurative language to convey imagery. 
Often considered poetic prose it is formatted in free verse and on vignette can include several short stanzas. 
For multiple vignettes each should be labeled by a number or letter, most commonly roman numerals.
According to Poetry Magnum Opus,
a Vignette, Old French, is a brief descriptive verse. This is a genre of verse that uses clear and detailed images to paint a picture of a moment in time.
A vignette is usually short and focused. The frame of the Vignette is at the discretion of the poet. A syllabic verse form also called a Vignette* is one of the many frames a poet might choose.
My example
Bereft (vignette)

Inellectually I am
aware the meter matters
and would like my poems to sound
as though a poet had dropped by

But within my head
I have no metronome
and when the dictionary
gives alternates for stress
or worse, shows none at a
I’m lost


A missing gene perhaps?
It’s sad to encounter
the silence of the iambs

 (c) Lawrencealot – February 16, 2013