sitter

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. One that sits, especially:
2. n. A person who cares for young children when the parents are not home; a babysitter.
3. n. A person who poses or models, as for a portrait.
4. n. A brooding hen.

Century Dictionary and Cyclopedia

1. n. One who or that which sits One who occupies a seat, or has a sitting posture.
2. n. A brooding or incubating bird.
3. n. One who takes a certain posture, position, or course in order to a particular end; specifically, one who poses to an artist for a portrait, bust, or the like.
4. n. One who watches during the night.
5. n. In cricket: An easy catch missed by a fielder.
6. n. A fielder who misses such a catch.

Wiktionary

1. n. Someone who sits e.g. for a portrait.
2. n. One employed to watch or tend something; the general form of babysitter, housesitter, petsitter, etc.
3. n. A broody hen.
4. n. A really easy scoring chance.

GNU Webster's 1913

1. n. One who sits; esp., one who sits for a portrait or a bust.
2. n. A bird that sits or incubates.

WordNet 3.0

1. n. a person engaged to care for children when the parents are not home
2. n. a domestic hen ready to brood
3. n. Dutch astronomer who calculated the size of the universe and suggested that it is expanding (1872-1934)
4. n. an organism (person or animal) that sits
5. n. a person who poses for a painter or sculptor