Sitter > define

noun

• Dutch astronomer who calculated the size of the universe and suggested that it is expanding (1872-1934.
  • synonyms: Willem de Sitter
• An organism (person or animal) that sits.
• A person engaged to care for children when the parents are not home.
  • synonyms: babysitter, baby-sitter
• A person who poses for a painter or sculptor.
  • synonyms: artist's model
• A domestic hen ready to brood.
  • synonyms: brood hen, broody, broody hen, setting hen

• (n.) A bird that sits or incubates.
• (n.) One who sits; especially, one who sits for a portrait or a bust.