位冠[ikan] ancient headgear showing rank
衣冠[ikan] kimono and ancient head-dress
栄冠[eikan] laurels
王冠[oukan] crown
加冠[kakan] crowning a boy with a traditional cap for the first time at a coming-of-age ceremony

花冠[kakan] corolla (of flower)
冠を曲げる[kanmuriwomageru] to become displeased
冠位[kani] system indicating court ranks by headgear colors (colours)
冠婚葬祭[kankonsousai] important ceremonial occasions in family relationships
冠詞[kanshi] article

か弱い[kayowai] frail
ひ弱い[hiyowai] weak
意志薄弱[ishihakujaku] weak-willed
胃弱[ijaku] dyspepsia
虚弱[kyojaku] feebleness

強弱[kyoujaku] strength
弱い[yowai] weak
弱い者[yowaimono] weak person
弱い相互作用[yowaisougosayou] weak interaction (physics)