dual
英 ['djuːəl]
美['dʊəl]
	    - adj. 双的;双重的
 - n. 双数;双数词
 - n. (Dual)人名;(法)迪阿尔
 
英英释意
- 1. consisting of or involving two parts or components usually in pairs;
 - "an egg with a double yolk"
 - "a double (binary) star"
 - "double doors"
 - "dual controls for pilot and copilot"
 - "duple (or double) time consists of two (or a multiple of two) beats to a measure"
 
- 2. having more than one decidedly dissimilar aspects or qualities;
 - "a double (or dual) role for an actor"
 - "the office of a clergyman is twofold; public preaching and private influence"- R.W.Emerson
 - "every episode has its double and treble meaning"-Frederick Harrison
 
- 3. a grammatical number category referring to two items or units as opposed to one item (singular) or more than two items (plural);
 - "ancient Greek had the dual form but it has merged with the plural form in modern Greek"