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

挂冠[keikan] resigning from a government post