y noun
plural y's or ys or Y's or Ys /ˈwaɪz/ plural y's or ys or Y's or Ys /ˈwaɪz/ Learner's definition of Y
1
: the 25th letter of the English alphabet英语字母表的第25个字母 [count]
[noncount]
2
[noncount] mathematics —
used to represent especially a second unknown quantity表示第二个未知数 3
[noncount] —
used in the phrase x, y, and z to refer to the second thing in a group of three unnamed things用于短语x,y,and z,表示一组三个未名事物中的第二个 4
[count] : something that is shaped like a Y*Y形的东西 5
the Y US, informal : the YMCA or the YWCA基督教青年会;基督教女青年会