boundary

/ˈbaʊndəri/
noun
  1. A line or limit that marks the edge of an area or separates two areas.
    • The surveyor marked the boundary with small flags.
    • The river forms the natural boundary between the two countries.
    • We put a fence along the boundary of our property.
  2. A limit of a subject, activity, or experience.
    • Scientists are pushing the boundaries of human knowledge.
    • The artist's work explores the boundary between reality and imagination.
    • It's important to set clear boundaries in a relationship.
  3. In sports, the line that marks the edge of the playing area, or a hit that reaches or crosses that line (especially in cricket).
    • The batsman hit the ball for a boundary, scoring four runs.
    • The player stepped over the boundary line, so the point didn't count.
    • Fans cheered as the ball sailed over the boundary for six.
Antonyms
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