鉄兜[tetsukabuto] steel helmet
兜虫[kabutomushi] rhinoceros beetle (esp. the Japanese rhinoceros beetle, Trypoxylus dichotomus)
内兜[uchikabuto] inside of a helmet
兜蟹[kabutogani] horseshoe crab
鳥兜[torikabuto] aconite (esp. species Aconitum japonicum)

兜頭巾[kabutozukin] helmet-shaped hood
兜率天[tosotsuten] Tusita heaven
勝って兜の緒を締めよ[kattekabutonoowoshimeyo] don't let your guard down even after a victory
角兜[tsunokabuto] spiked helmet

黄鉄鉱[outekkou] iron pyrites
可鍛鉄[katantetsu] malleable iron
狭軌鉄道[kyoukitetsudou] narrow-gauge railway
近鉄[kintetsu] Kinki Nippon Tetsudou (railway co.)
剣付き鉄砲[kentsukideppou] fixed bayonet

甲鉄[koutetsu] armor
甲鉄艦[koutetsukan] armored ship
甲鉄板[koutetsuban] armor plate
鋼鉄[koutetsu] steel
国鉄[kokutetsu] national railway (esp. Japan National Railways)