sitter

noun

1. 1

   Dutch astronomer who calculated the size of the universe and suggested that it is expanding (1872-1934)

2. 2

   a domestic hen ready to brood

3. 3

   a person who poses for a painter or sculptor

4. 4

   a person engaged to care for children when the parents are not home

5. 5

   an organism (person or animal) that sits