兜 - helmet, head piece

helmet (of a warrior); headpiece

horseshoe crab

Tusita heaven (one of the six heavens of the desire realm); Tushita

tokin; small black headgear worn by yamabushi

to accept one's inferiority; to take one's hat off to someone

inside of a helmet; hidden circumstances

frot (sex act)

spiked helmet

Hercules beetle (Dynastes hercules)

tadpole shrimp (Triopsidae spp.); shield shrimp

Kabutochō (neighbourhood of Nihonbashi, Tokyo, where the Tokyo Stock Exchange is located)

zunari helmet (made from 3-5 pieces of metal)