noun
issuing (an order); handing down (a command)
Used almost exclusively in the pattern 命令一下 (めいれいいっか) meaning 'as soon as the order is given' or 'upon the issuance of an order'. It is a formal, somewhat literary expression.
See also: 命令一下 (めいれいいっか)
命令一下、部隊は直ちに出動した。
As soon as the order was given, the unit immediately deployed.
命令一下、全員が持ち場についた。
Upon the issuance of the order, everyone took their positions.