boundary(redirected from Natural boundary)
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bound•a•ry(ˈbaʊn də ri, -dri)
n., pl. -ries.
border frontier boundary
The border between two countries is the dividing line between them.
A frontier is a border with official points for people to cross, often with guards.
You talk about one country's border or frontier with another.
The boundary of a region or area of land is its outer edge.
Don't talk about the 'boundary' of a country. Instead you talk about its borders.
|Noun||1.||boundary - the line or plane indicating the limit or extent of something|
hairline - the natural margin formed by hair on the head
frontier - an international boundary or the area (often fortified) immediately inside the boundary
heliopause - the boundary marking the edge of the sun's influence; the boundary (roughly 100 AU from the sun) between the interplanetary medium and the interstellar medium; where the solar wind from the sun and the radiation from other stars meet
district line - the boundary between two districts
county line - the boundary between two counties
city line - the boundary of a city
end - a boundary marking the extremities of something; "the end of town"
extremity - the outermost or farthest region or point
surface - the extended two-dimensional outer boundary of a three-dimensional object; "they skimmed over the surface of the water"; "a brush small enough to clean every dental surface"; "the sun has no distinct surface"
shoreline - a boundary line between land and water
|2.||boundary - a line determining the limits of an area|
line - a length (straight or curved) without breadth or thickness; the trace of a moving point
rim - the shape of a raised edge of a more or less circular object
upper bound - (mathematics) a number equal to or greater than any other number in a given set
lower bound - (mathematics) a number equal to or less than any other number in a given set
thalweg - the middle of the chief navigable channel of a waterway that forms the boundary line between states
|3.||boundary - the greatest possible degree of something; "what he did was beyond the bounds of acceptable behavior"; "to the limit of his ability"|
extent - the distance or area or volume over which something extends; "the vast extent of the desert"; "an orchard of considerable extent"
knife-edge - a narrow boundary; "he lived on a knife-edge between genius and insanity"
absoluteness, starkness, utterness - the quality of being complete or utter or extreme; "the starkness of his contrast between justice and fairness was open to many objections"