a real or imagined line that marks the limits or edges of something and separates it from other things or places; a dividing line 边界；界限；分界线 After the war the national boundaries were redrawn. 战后重新划定了国界。 - (British English)
county boundaries 郡界 boundary changes/disputes 边界变化／争端 The fence marks the boundary between my property and hers. 那道篱笆是我和她的住宅之间的分界。 Scientists continue to push back the boundaries of human knowledge. 科学家不断扩大人类知识的范围。 It is up to the teacher to set the boundary between acceptable and unacceptable behaviour. 划清可为与不可为之间的界限是老师的职责。 He could just see her beyond the boundary wall of the cemetery. 他只能在墓地的界墙外看到她。 to extend the boundaries of high art to include some popular music 扩大高雅艺术的范围，包括一些流行音乐
Synonyms borderborder- boundary
- frontier
- border the line that separates two countries or areas; the land near this line:
a national park on the border between Kenya and Tanzania 位于肯尼亚和坦桑尼亚边界的国家公园
- boundary a line that marks the edges of an area of land and separates it from other areas:
The fence marked the boundary between my property and hers. 那道篱笆曾是我和她的房产之间的地界。
- frontier (British English)
the line that separates two countries or areas; the land near this line: 指国界、边界、边疆、边界地区： The river formed the frontier between the land of the Saxons and that of the Danes. 这条河曾是撒克逊人与古斯堪的纳维亚人土地的分界线。
The point where you cross from one country to another is usually called the border. In British English it can also be called the frontier, but this is often in a context of wildness, danger and uncertainty: 国界线通常叫 border；英式英语亦可叫 frontier，但 frontier 常与荒芜、危险和不确定联系在一起： The rebels control the frontier and the surrounding area. 叛乱分子控制了边疆地区。
地图上标示的国界线可叫 boundary，但穿越国界不用 boundary： After the war the national boundaries were redrawn. 战后重新划定了国界。 - Thousands of immigrants cross the boundary every day.
the boundary fence/wall between the properties 分隔两所房子的篱笆／墙
- across/along/on/over a/the border/boundary/frontier
- at the boundary/frontier
- the border/boundary/frontier with a place
- the northern/southern/eastern/western border/boundary/frontier
- a national/common/disputed border/boundary/frontier
Extra ExamplesTopics Gardensc1His policies appeal across party political boundaries. 他的政策感召力超越了党派政治界限。 In her performance she had clearly overstepped the boundaries of good taste. 很显然她的表演品位流于庸俗。 She had never strayed beyond the city boundaries. 她从未出过这个城市。 The internet has blurred the boundary between news and entertainment. 因特网模糊了新闻与娱乐的界限。 The boundary was fixed just south of the farm. 边界就定在农场南面。 The river forms the boundary. 这条河形成了边界。 The state has a boundary with Ontario. 这个州和安大略省相邻。 They drove across the boundary. 他们开车穿过边界。 This goes beyond the boundaries of what is accepted. 这超出了能接受的界限。 This job crosses the traditional boundary between social work and healthcare. 这项工作跨越了社会工作与医疗保健之间的传统界限。 We continued along the southern boundary of the county. 我们继续沿着该郡南部边境前进。 We had to stop at the boundary. 我们不得不在边界停下。 We've just crossed the boundary into Sussex. 我们刚刚穿过边界进入苏塞克斯郡。 a boundary dispute between Brazil and Paraguay 巴西与巴拉圭的边界之争 a boundary dispute with their neighbours 他们与邻国的边界之争 keeping within the boundaries of the law 保持在法律规定的范围内 on the boundary of physics and chemistry 在物理与化学的学科边缘 research which extends the boundaries of human knowledge 拓展了人类知识范围的研究 the boundary between Sussex and Surrey 萨塞克斯郡和萨里郡之间的边界 the boundary between sanity and insanity 神志正常与不正常的分界线 within the boundaries of the old city walls 在老城墙的范围以内 Our aim is to extend the boundaries of high art to include some popular music. 我们的目标是扩大高级艺术的范围，包括一些流行音乐。 Three settlers were killed in a boundary dispute last week. 三个移民上周在边界争端中遇害。
Oxford Collocations Dictionaryadjective- common
- northern
- southern
- …
- have
- form
- mark
- …
- fence
- hedge
- line
- …
- across the boundary
- over the boundary
- along the boundary
- …
(in cricket 板球 a hit of the ball that crosses the boundary of the playing area and scores extra points 使球越过边界线的击球（得加分） He hit 13 boundaries from 183 balls. 他从183个球打到13个界。
Word Originearly 17th cent.: variant of dialect bounder, from bound ‘boundary’ + -er, perhaps on the pattern of limitary.
Idioms
push the boundaries/limits
to attempt to go beyond what is allowed or thought to be possible 界限： 试图超越允许或认为可能的范围We aim to push the boundaries of what we can achieve. 我们的目标是超越我们所能达到的极限。 She pushes her physical limits through various endurance challenges. 她通过各种耐力挑战来突破自己的身体极限。