凹ます[hekomasu] to dent
凹ませる[hekomaseru] to dent
凹まる[kubomaru] to be low (as a hollow)
凹む[hekomu] to be dented
凹める[kubomeru] to hollow out

凹レンズ[ourenzu] concave lens
凹眼[ougan] cavernous eyes
凹眼鏡[ougankyou] concave glasses
凹型[ougata] concavity

於多福[otafuku] homely woman (esp. one with a small low nose, high flat forehead, and bulging cheeks)
圧倒的多数[attoutekitasuu] overwhelming numbers
一妻多夫[issaitafu] polyandry
一番多い[ichibanooi] most numerous
一夫多妻[ipputasai] polygamy

引く手数多[hikuteamata] being very popular
過多[kata] excess
幾多[ikuta] many
ご多忙中[gotabouchuu] in the midst of your work (often used as a formal phrase in business letters, etc.)
好事魔多し[koujimaooshi] Lights are usually followed by shadows