baby-sit

UK: ˈbeɪbi sɪt | US: ˈbeɪbi sɪt

Definition
  1. vi. to temporarily care for a child in the absence of parents or guardians

  2. vt. to act as a temporary caretaker for (a child)

Structure
baby <infant>sit <to watch>
Etymology

The term "baby-sit" emerged in the early 20th century (1937, first recorded in the US) as a back-formation from "baby-sitter." It combines "baby" (from Middle English babi, imitative of infant speech) and "sit" (Old English sittan, meaning "to occupy a seat" or "to keep watch"). The logic reflects the sitter’s role as a guardian who "keeps watch" over a child. The hyphenated form preserves the original compound structure.

Examples
  1. She often baby-sits for her neighbors on weekends.

  2. Can you baby-sit my son while I attend the meeting?

  3. Teenagers commonly baby-sit to earn extra money.

  4. They hired a trusted student to baby-sit their toddler.

  5. The training course teaches how to baby-sit safely.