sitter

UK: ˈsɪtə | US: ˈsɪtər

Definition
  1. n. a person who sits, especially for a portrait or examination

  2. n. a person employed to care for children, pets, or a house temporarily (short for "babysitter" or "housesitter")

  3. n. a bird that remains on its nest to incubate eggs

Structure
sit <to rest on the lower body>er <agent noun suffix (person who does the action)>
Etymology

The word "sitter" originates from the Old English verb "sittan," meaning "to sit." The suffix "-er" is a productive agentive suffix in English, used to form nouns indicating a person who performs an action (e.g., "runner," "writer"). Over time, "sitter" evolved to describe not only someone who sits but also someone who performs tasks while seated or present (e.g., babysitting, house-sitting). The avian sense reflects the literal act of a bird sitting on eggs.

Examples
  1. The artist asked the sitter to remain still for the portrait.

  2. We hired a sitter to watch the kids while we attended the event.

  3. The robin is a diligent sitter, rarely leaving its nest.

  4. She works as a pet sitter on weekends.

  5. The exam sitter nervously tapped his pencil on the desk.