Appositives are nouns or a group of words used often with modifiers.
An appositive phrase usually follows the word it explains or identifies, but it may also precede it. E.g. My cat, a fluffy white little kitten, is really naughty today E.g. An advocate of feminism, Carla didn’t want to hear any of his weird views.
Some links…
- Grammar Girl - for Extra info extra commas are used with appositives
- Owl English at Purdue