empty set

US 
UK 
  • un.空队列;空集
  • Web空集合
un.
1.
空队列
2.
空集

Sample Sentence

Definition:
Category:AllAll,OralOral,WrittenWritten,TitleTitle,TechnicalTechnical
Source:AllAll,DictionaryDictionary,WebWeb
Difficulty:AllAll,EasyEasy,MiddleMiddle,HardHard