安全保障[anzenhoshou] security guarantee (e.g. military security, network security, etc.)
安全保障条約[anzenhoshoujouyaku] US-Japan Security Treaty
安保[anpo] US-Japan Security Treaty
医療保険[iryouhoken] medical-care insurance
火災保険[kasaihoken] fire insurance

火保ち[himochi] fire-holding qualities
過保護[kahogo] overprotective
確保[kakuho] guarantee
環境保護論者[kankyouhogoronsha] environmentalist
機密保護[kimitsuhogo] security (e.g. data, password, etc.)

橋頭堡[kyoutouho] bridgehead
五稜堡[goryouho] five-sided fort
堡礁[hoshou] barrier reef

堡塁[hourui] fort
海堡[kaihou] breakwater

一本橋[ipponbashi] (a) log bridge
仮橋[karibashi] temporary bridge
可動橋[kadoukyou] movable bridge
艦橋[kankyou] bridge (e.g. on a warship)
丸木橋[marukibashi] log bridge

橋脚[kyoukyaku] bridge pier
橋脚舟[kyoukyakushuu] pontoon
橋渡し[hashiwatashi] bridge building
橋頭保[kyoutouhou] bridgehead

データの先頭[deetanosentou] beginning of data
一頭[ittou] one large animal (horses, cattle, etc.)
一頭立て[ittoudate] one-horse (carriage)
咽頭[intou] pharynx
駅頭[ekitou] station

音頭[ondo] leading a group of people
会頭[kaitou] society president
街頭[gaitou] in the street
核弾頭[kakudantou] nuclear warhead
巻頭[kantou] opening page of book