What is the synonym word of 'Indeterminate'?

Indeterminate (adjective):
English Meaning: Not clearly determined or established.
Bangla Meaning: অনির্দিষ্ট, যে রাশির কোনো নির্দিষ্ট মূল্য নেই; অনির্দিষ্ট রাশি, অনির্ণেয়।
Synonyms: Undetermined, Unpredictable, Vague,  Indefinite, Unspecific.
Antonyms: Known, Definite,  Clear, Decisive, Definable.
Other Forms: 
- Indeterminable (adjective).
- Indeterminably (adverb)
- Indetermination (Noun)
Example Sentence:
1. He seems to be being asked to look at what industry might need at some indeterminate time in the future.
2. Juvenile criminals are sometimes sentenced to indeterminate prison terms rather than a fixed length of time.