Or to gum!
Literally: oneself – warrior – person – gauze
Alternately: Fixated on a goal to the point of blinding oneself to everything else. Charging ahead without looking to see what else is coming or what lies in one’s wake. Madcap; reckless; frantic.
Notes: This one’s got an interesting etymology. It was originally 我 plus 貪 (musabori, from a verb meaning “to lust after,” “to devour greedily”). Phonetic drift turned gamusabori into gamusha, which kept the 我 and received the ateji 武者. Later on, the suffix ら was added – apparently in its function of expressing a condition or situation – and given its own ateji with 羅. It is therefore not inappropriate that the whole phrase may be found expressed in kana.
This four-character compound may be shortened to three, dropping the final 羅. Amusingly, a reckless person may be called a 我武者者 (gamusha mono).