undetermined 

英汉解释

adj. 待定的；未确定的；缺乏决断力的；未解决的

同义词

a. indeterminate，open，undecided，unresolved

反义词

a.   determinate，determined

参考例句

1. The other 27 cases remained undetermined due to insufficient data.
另外27例因资料不足而无法确定传播方式。
2. For an undetermined period of time I felt myself cut off from the world, as an abstract spectator.
有一段时间，我恍惚地感到自己从世界中分离了出来，成为一个抽象的旁观者。

英英解释

adj.
  1. not yet having been ascertained or determined
  2. not precisely determined or established; not fixed or known in advance
  3. not brought to a conclusion; subject to further thought

网络释义

undetermined
未定的; 未确定的; 不确定; 待定的;
Undetermined coefficients
未定系数; 未定系数法;
undetermined etiology
释义：未确定的病因学;
undetermined eoefficient
未定系数; 待定系数;
undetermined origin
释义：未明来源,原因未定;