• 結婚けっこん — marriage
• 結束けっそく — unity, solidarity
• 団結だんけつ — unity, union
• 結論けつろん — conclusion
• 結果けっか — result
• 結むすび目め — knot

“結” is a common kanji in both literal and abstract senses — from tying a knot (結ぶ) to forming relationships (結婚) or conclusions (結論). It’s widely used in everyday Japanese and conveys the idea of bringing things together or finalizing something.

彼かれは 彼女かのじょと 結婚けっこんしました。
He got married to her.

その会議かいぎは 結論けつろんが 出でませんでした。
The meeting ended without a conclusion.

On-yomi ケツ is used in compound words like 結果 and 結婚. The kun-yomi むすぶ is commonly used in daily speech, especially in physical or abstract "tying together" situations.