The best replacement for conclusion is summary.

The best alternatives to conclusion are rated as following:
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★★★★  conclusions
★★★★  inference
★★★  discussion
★★  evaluation
★★  generalization
★★  recommendation
★★  premise
★  recommendation which comes first
★  results
★  abstract
★  resolution
★  evaluation first
★  epilogue
  hypothesis
  executive summary
  denouement
  in conclusion
  observation
  making inferences
  to conclude

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Speaking about conclusion, one probably shouldn't forget about premise.

Other search terms related to conclusion and their ratings are:
★★★★★ premise
★★★★ using in conclusion
★ hypothesis
★ in conclusion
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