Synonyms for Complete:
General:
* Finished
* Done
* Ended
* Whole
* Entire
* Full
* Perfect
* Consummate
* Thorough
* Comprehensive
* Exhaustive
* Total
* Absolute
* Ultimate
* Final
* Concluded
More specific:
* Accomplished (referring to tasks)
* Realized (referring to goals)
* Achieved (referring to success)
* Executed (referring to plans)
* Fulfilled (referring to desires)
* Satisfied (referring to needs)
* Resolved (referring to problems)
Antonyms for Complete:
General:
* Incomplete
* Partial
* Unfinished
* Imperfect
* Deficient
* Lacking
* Insufficient
* Inadequate
* Limited
* Unfinished
More specific:
* Unfulfilled (referring to desires)
* Unsatisfied (referring to needs)
* Unresolved (referring to problems)
* Aborted (referring to tasks)
* Abandoned (referring to projects)
The best synonym or antonym will depend on the context in which you're using the word "complete."