border

noun

• 1a line separating two political or geographical areas, especially countries:the German border with Denmark [as modifier]:border patrols
• a district near a line separating two political or geographical areas:a refugee camp on the border

• 2the edge or boundary of something, or the part near it:the northern border of their distribution area figurativethe unknown regions at the borders of physics and electronics

• 3a band or strip, especially a decorative one, around the edge of something:put a white border around the picture
• a strip of ground along the edge of a lawn or path for planting flowers or shrubs:the garden borders are planted with perennials

verb

• form an edge along or beside (something):a pool bordered by palm trees
• (of a country or area) be adjacent to (another country or area):regions bordering Azerbaijan [no object]:the park is east of San Diego, bordering on Mexico
• [no object] (border on) be close to an extreme condition:Sam arrived in a state of excitement bordering on hysteria
• (usually be bordered with) provide (something) with a decorative edge:a curving driveway bordered with chrysanthemums