行軍 is read as こうぐん (kougun) and means march.
こうぐん
kougun
きょうこうぐん
doing something on a very strict schedule
ぐんじこうどう
military movements
ぐんたいこうしんきょく
military march
いきとどく
to be scrupulous
いきづまり
deadlock
いきづまる
to come to a dead end
ぎょうかく
administrative reform
ぎょうせいかんりちょう
Administrative Management Agency
ぐん
military authorities
くうぐん
air force
かいぐん
navy
しょうぐん
general