Here are some examples:
* "Marginalized groups" (The noun "groups" is being modified by the adjective "marginalized.")
* "The marginalized are often overlooked." (The adjective "marginalized" is used as the subject of the sentence.)
However, it can also be used as a verb:
* "Society has marginalized certain people."
The meaning of the word is slightly different depending on whether it is used as an adjective or a verb.