Vignettes are short, impressionistic scenes that focus on one moment or give a trenchant impression about a character or an idea. It could describe a scene or even describe a situation involving action. A vignette points to a style rather than any form.
Example
SHOWDOWN
The hand
ticks toward noon,
main street quiets,
a voice call out -
make my day
Brian Strand
[n] a small illustrative sketch (as sometimes placed at the beginning of chapters in books)
[n] a photograph whose edges shade off gradually
[n] a brief literary description