/ˈbaʊndri ||; ˈbaυndrɪ/noun [C] (plural boundaries) a real or imagined line that marks the limits of sth and divides it from other places or things （真实或想象中的）界限，分界线: The main road is the boundary between the two districts. 这条大路是两区的分界。Scientists continue to push back the boundaries of human knowledge. 科学家不断扩展人类知识的界限。 ☞Look at the note at border. 参看 border 的注释。