蟷螂の斧

Etymology
Literally “praying mantis’s axe”, alluding to a parable in  about a praying mantis attempting to stop an emperor’s carriage. See for details.

Noun

 * 1) a reckless strike above one’s strength or proper station
 * 2) a brave individual who faces stronger enemies
 * 1) a brave individual who faces stronger enemies
 * 1) a brave individual who faces stronger enemies