A person who is begging for money on a street corner is an example of a mendicant.
A person who is continually pleading for things is an example of a mendicant person.
Origin of mendicant
- Middle English from Old French from Latin mendīcāns mendīcant- present participle of mendīcāre to beg from mendīcus needy, beggar from mendum physical defect
From American Heritage Dictionary of the English Language, 5th Edition