• 結婚けっこん — marriage
• 再婚さいこん — remarriage
• 新婚しんこん — newly married
• 未婚みこん — unmarried
• 既婚きこん — married (status)
• 婚約こんやく — engagement
• 婚礼こんれい — wedding ceremony
• 婚姻こんいん — matrimony; marriage (legal term)
• 婚活こんかつ — spouse-hunting / looking for a partner
• 婚期こんき — (ideal) age/time for marriage

婚 uses the radical 女 and the phonetic 昏 (dusk). Many old wedding rites took place toward evening, so together they picture the joining at dusk — hence “marriage.”